1.. SPDX-License-Identifier: CC-BY-SA-2.0-UK 2 3****************** 4Variables Glossary 5****************** 6 7This chapter lists common variables used in the OpenEmbedded build 8system and gives an overview of their function and contents. 9 10:term:`A <ABIEXTENSION>` :term:`B` :term:`C <CACHE>` 11:term:`D` :term:`E <EFI_PROVIDER>` :term:`F <FEATURE_PACKAGES>` 12:term:`G <GCCPIE>` :term:`H <HOMEPAGE>` :term:`I <ICECC_DISABLED>` 13:term:`K <KARCH>` :term:`L <LABELS>` :term:`M <MACHINE>` 14:term:`N <NATIVELSBSTRING>` :term:`O <OBJCOPY>` :term:`P` 15:term:`R <RANLIB>` :term:`S` :term:`T` 16:term:`U <UBOOT_CONFIG>` :term:`V <VOLATILE_LOG_DIR>` 17:term:`W <WARN_QA>` :term:`X <XSERVER>` 18 19.. glossary:: 20 :sorted: 21 22 :term:`ABIEXTENSION` 23 Extension to the Application Binary Interface (ABI) field of the GNU 24 canonical architecture name (e.g. "eabi"). 25 26 ABI extensions are set in the machine include files. For example, the 27 ``meta/conf/machine/include/arm/arch-arm.inc`` file sets the 28 following extension:: 29 30 ABIEXTENSION = "eabi" 31 32 :term:`ALLOW_EMPTY` 33 Specifies whether to produce an output package even if it is empty. 34 By default, BitBake does not produce empty packages. This default 35 behavior can cause issues when there is an 36 :term:`RDEPENDS` or some other hard runtime 37 requirement on the existence of the package. 38 39 Like all package-controlling variables, you must always use them in 40 conjunction with a package name override, as in:: 41 42 ALLOW_EMPTY:${PN} = "1" 43 ALLOW_EMPTY:${PN}-dev = "1" 44 ALLOW_EMPTY:${PN}-staticdev = "1" 45 46 :term:`ALTERNATIVE` 47 Lists commands in a package that need an alternative binary naming 48 scheme. Sometimes the same command is provided in multiple packages. 49 When this occurs, the OpenEmbedded build system needs to use the 50 alternatives system to create a different binary naming scheme so the 51 commands can co-exist. 52 53 To use the variable, list out the package's commands that are also 54 provided by another package. For example, if the ``busybox`` package 55 has four such commands, you identify them as follows:: 56 57 ALTERNATIVE:busybox = "sh sed test bracket" 58 59 For more information on the alternatives system, see the 60 ":ref:`ref-classes-update-alternatives`" 61 section. 62 63 :term:`ALTERNATIVE_LINK_NAME` 64 Used by the alternatives system to map duplicated commands to actual 65 locations. For example, if the ``bracket`` command provided by the 66 ``busybox`` package is duplicated through another package, you must 67 use the :term:`ALTERNATIVE_LINK_NAME` variable to specify the actual 68 location:: 69 70 ALTERNATIVE_LINK_NAME[bracket] = "/usr/bin/[" 71 72 In this example, the binary for the ``bracket`` command (i.e. ``[``) 73 from the ``busybox`` package resides in ``/usr/bin/``. 74 75 .. note:: 76 77 If :term:`ALTERNATIVE_LINK_NAME` is not defined, it defaults to ``${bindir}/name``. 78 79 For more information on the alternatives system, see the 80 ":ref:`ref-classes-update-alternatives`" 81 section. 82 83 :term:`ALTERNATIVE_PRIORITY` 84 Used by the alternatives system to create default priorities for 85 duplicated commands. You can use the variable to create a single 86 default regardless of the command name or package, a default for 87 specific duplicated commands regardless of the package, or a default 88 for specific commands tied to particular packages. Here are the 89 available syntax forms:: 90 91 ALTERNATIVE_PRIORITY = "priority" 92 ALTERNATIVE_PRIORITY[name] = "priority" 93 ALTERNATIVE_PRIORITY_pkg[name] = "priority" 94 95 For more information on the alternatives system, see the 96 ":ref:`ref-classes-update-alternatives`" 97 section. 98 99 :term:`ALTERNATIVE_TARGET` 100 Used by the alternatives system to create default link locations for 101 duplicated commands. You can use the variable to create a single 102 default location for all duplicated commands regardless of the 103 command name or package, a default for specific duplicated commands 104 regardless of the package, or a default for specific commands tied to 105 particular packages. Here are the available syntax forms:: 106 107 ALTERNATIVE_TARGET = "target" 108 ALTERNATIVE_TARGET[name] = "target" 109 ALTERNATIVE_TARGET_pkg[name] = "target" 110 111 .. note:: 112 113 If :term:`ALTERNATIVE_TARGET` is not defined, it inherits the value 114 from the :term:`ALTERNATIVE_LINK_NAME` variable. 115 116 If :term:`ALTERNATIVE_LINK_NAME` and :term:`ALTERNATIVE_TARGET` are the 117 same, the target for :term:`ALTERNATIVE_TARGET` has "``.{BPN}``" 118 appended to it. 119 120 Finally, if the file referenced has not been renamed, the 121 alternatives system will rename it to avoid the need to rename 122 alternative files in the :ref:`ref-tasks-install` 123 task while retaining support for the command if necessary. 124 125 For more information on the alternatives system, see the 126 ":ref:`ref-classes-update-alternatives`" section. 127 128 :term:`ANY_OF_DISTRO_FEATURES` 129 When inheriting the :ref:`ref-classes-features_check` 130 class, this variable identifies a list of distribution features where 131 at least one must be enabled in the current configuration in order 132 for the OpenEmbedded build system to build the recipe. In other words, 133 if none of the features listed in :term:`ANY_OF_DISTRO_FEATURES` 134 appear in :term:`DISTRO_FEATURES` within the current configuration, then 135 the recipe will be skipped, and if the build system attempts to build 136 the recipe then an error will be triggered. 137 138 :term:`APPEND` 139 An override list of append strings for each target specified with 140 :term:`LABELS`. 141 142 See the :ref:`ref-classes-grub-efi` class for more 143 information on how this variable is used. 144 145 :term:`AR` 146 The minimal command and arguments used to run ``ar``. 147 148 :term:`ARCHIVER_MODE` 149 When used with the :ref:`ref-classes-archiver` class, 150 determines the type of information used to create a released archive. 151 You can use this variable to create archives of patched source, 152 original source, configured source, and so forth by employing the 153 following variable flags (varflags):: 154 155 ARCHIVER_MODE[src] = "original" # Uses original (unpacked) source files. 156 ARCHIVER_MODE[src] = "patched" # Uses patched source files. This is the default. 157 ARCHIVER_MODE[src] = "configured" # Uses configured source files. 158 ARCHIVER_MODE[diff] = "1" # Uses patches between do_unpack and do_patch. 159 ARCHIVER_MODE[diff-exclude] ?= "file file ..." # Lists files and directories to exclude from diff. 160 ARCHIVER_MODE[dumpdata] = "1" # Uses environment data. 161 ARCHIVER_MODE[recipe] = "1" # Uses recipe and include files. 162 ARCHIVER_MODE[srpm] = "1" # Uses RPM package files. 163 164 For information on how the variable works, see the 165 ``meta/classes/archiver.bbclass`` file in the :term:`Source Directory`. 166 167 :term:`AS` 168 Minimal command and arguments needed to run the assembler. 169 170 :term:`ASSUME_PROVIDED` 171 Lists recipe names (:term:`PN` values) BitBake does not 172 attempt to build. Instead, BitBake assumes these recipes have already 173 been built. 174 175 In OpenEmbedded-Core, :term:`ASSUME_PROVIDED` mostly specifies native 176 tools that should not be built. An example is ``git-native``, which 177 when specified, allows for the Git binary from the host to be used 178 rather than building ``git-native``. 179 180 :term:`ASSUME_SHLIBS` 181 Provides additional ``shlibs`` provider mapping information, which 182 adds to or overwrites the information provided automatically by the 183 system. Separate multiple entries using spaces. 184 185 As an example, use the following form to add an ``shlib`` provider of 186 shlibname in packagename with the optional version:: 187 188 shlibname:packagename[_version] 189 190 Here is an example that adds a shared library named ``libEGL.so.1`` 191 as being provided by the ``libegl-implementation`` package:: 192 193 ASSUME_SHLIBS = "libEGL.so.1:libegl-implementation" 194 195 :term:`AUTO_LIBNAME_PKGS` 196 When the :ref:`ref-classes-debian` class is inherited, 197 which is the default behavior, :term:`AUTO_LIBNAME_PKGS` specifies which 198 packages should be checked for libraries and renamed according to 199 Debian library package naming. 200 201 The default value is "${PACKAGES}", which causes the 202 :ref:`ref-classes-debian` class to act on all packages that are 203 explicitly generated by the recipe. 204 205 :term:`AUTOREV` 206 When :term:`SRCREV` is set to the value of this variable, it specifies to 207 use the latest source revision in the repository. Here is an example:: 208 209 SRCREV = "${AUTOREV}" 210 211 If you use the previous statement to retrieve the latest version of 212 software, you need to be sure :term:`PV` contains 213 ``${``\ :term:`SRCPV`\ ``}``. For example, suppose you have a kernel 214 recipe that inherits the :ref:`ref-classes-kernel` class and you 215 use the previous statement. In this example, ``${SRCPV}`` does not 216 automatically get into :term:`PV`. Consequently, you need to change 217 :term:`PV` in your recipe so that it does contain ``${SRCPV}``. 218 219 For more information see the 220 ":ref:`dev-manual/packages:automatically incrementing a package version number`" 221 section in the Yocto Project Development Tasks Manual. 222 223 :term:`AUTO_SYSLINUXMENU` 224 Enables creating an automatic menu for the syslinux bootloader. You 225 must set this variable in your recipe. The 226 :ref:`ref-classes-syslinux` class checks this variable. 227 228 :term:`AVAILTUNES` 229 The list of defined CPU and Application Binary Interface (ABI) 230 tunings (i.e. "tunes") available for use by the OpenEmbedded build 231 system. 232 233 The list simply presents the tunes that are available. Not all tunes 234 may be compatible with a particular machine configuration, or with 235 each other in a 236 :ref:`Multilib <dev-manual/libraries:combining multiple versions of library files into one image>` 237 configuration. 238 239 To add a tune to the list, be sure to append it with spaces using the 240 "+=" BitBake operator. Do not simply replace the list by using the 241 "=" operator. See the 242 ":ref:`bitbake-user-manual/bitbake-user-manual-metadata:basic syntax`" section in the BitBake 243 User Manual for more information. 244 245 :term:`AZ_SAS` 246 Azure Storage Shared Access Signature, when using the 247 :ref:`Azure Storage fetcher (az://) <bitbake-user-manual/bitbake-user-manual-fetching:fetchers>` 248 This variable can be defined to be used by the fetcher to authenticate 249 and gain access to non-public artifacts:: 250 251 AZ_SAS = ""se=2021-01-01&sp=r&sv=2018-11-09&sr=c&skoid=<skoid>&sig=<signature>"" 252 253 For more information see Microsoft's Azure Storage documentation at 254 https://docs.microsoft.com/en-us/azure/storage/common/storage-sas-overview 255 256 :term:`B` 257 The directory within the :term:`Build Directory` in which the 258 OpenEmbedded build system places generated objects during a recipe's 259 build process. By default, this directory is the same as the 260 :term:`S` directory, which is defined as:: 261 262 S = "${WORKDIR}/${BP}" 263 264 You can separate the (:term:`S`) directory and the directory pointed to 265 by the :term:`B` variable. Most Autotools-based recipes support 266 separating these directories. The build system defaults to using 267 separate directories for ``gcc`` and some kernel recipes. 268 269 :term:`BAD_RECOMMENDATIONS` 270 Lists "recommended-only" packages to not install. Recommended-only 271 packages are packages installed only through the 272 :term:`RRECOMMENDS` variable. You can prevent any 273 of these "recommended" packages from being installed by listing them 274 with the :term:`BAD_RECOMMENDATIONS` variable:: 275 276 BAD_RECOMMENDATIONS = "package_name package_name package_name ..." 277 278 You can set this variable globally in your ``local.conf`` file or you 279 can attach it to a specific image recipe by using the recipe name 280 override:: 281 282 BAD_RECOMMENDATIONS:pn-target_image = "package_name" 283 284 It is important to realize that if you choose to not install packages 285 using this variable and some other packages are dependent on them 286 (i.e. listed in a recipe's :term:`RDEPENDS` 287 variable), the OpenEmbedded build system ignores your request and 288 will install the packages to avoid dependency errors. 289 290 This variable is supported only when using the IPK and RPM 291 packaging backends. DEB is not supported. 292 293 See the :term:`NO_RECOMMENDATIONS` and the 294 :term:`PACKAGE_EXCLUDE` variables for related 295 information. 296 297 :term:`BASE_LIB` 298 The library directory name for the CPU or Application Binary 299 Interface (ABI) tune. The :term:`BASE_LIB` applies only in the Multilib 300 context. See the ":ref:`dev-manual/libraries:combining multiple versions of library files into one image`" 301 section in the Yocto Project Development Tasks Manual for information 302 on Multilib. 303 304 The :term:`BASE_LIB` variable is defined in the machine include files in 305 the :term:`Source Directory`. If Multilib is not 306 being used, the value defaults to "lib". 307 308 :term:`BASE_WORKDIR` 309 Points to the base of the work directory for all recipes. The default 310 value is "${TMPDIR}/work". 311 312 :term:`BB_ALLOWED_NETWORKS` 313 Specifies a space-delimited list of hosts that the fetcher is allowed 314 to use to obtain the required source code. Following are 315 considerations surrounding this variable: 316 317 - This host list is only used if :term:`BB_NO_NETWORK` is either not set 318 or set to "0". 319 320 - There is limited support for wildcard matching against the beginning of 321 host names. For example, the following setting matches 322 ``git.gnu.org``, ``ftp.gnu.org``, and ``foo.git.gnu.org``:: 323 324 BB_ALLOWED_NETWORKS = "*.gnu.org" 325 326 .. note:: 327 328 The use of the "``*``" character only works at the beginning of 329 a host name and it must be isolated from the remainder of the 330 host name. You cannot use the wildcard character in any other 331 location of the name or combined with the front part of the 332 name. 333 334 For example, ``*.foo.bar`` is supported, while ``*aa.foo.bar`` 335 is not. 336 337 - Mirrors not in the host list are skipped and logged in debug. 338 339 - Attempts to access networks not in the host list cause a failure. 340 341 Using :term:`BB_ALLOWED_NETWORKS` in conjunction with 342 :term:`PREMIRRORS` is very useful. Adding the host 343 you want to use to :term:`PREMIRRORS` results in the source code being 344 fetched from an allowed location and avoids raising an error when a 345 host that is not allowed is in a :term:`SRC_URI` 346 statement. This is because the fetcher does not attempt to use the 347 host listed in :term:`SRC_URI` after a successful fetch from the 348 :term:`PREMIRRORS` occurs. 349 350 :term:`BB_BASEHASH_IGNORE_VARS` 351 See :term:`bitbake:BB_BASEHASH_IGNORE_VARS` in the BitBake manual. 352 353 :term:`BB_CACHEDIR` 354 See :term:`bitbake:BB_CACHEDIR` in the BitBake manual. 355 356 :term:`BB_CHECK_SSL_CERTS` 357 See :term:`bitbake:BB_CHECK_SSL_CERTS` in the BitBake manual. 358 359 :term:`BB_CONSOLELOG` 360 See :term:`bitbake:BB_CONSOLELOG` in the BitBake manual. 361 362 :term:`BB_CURRENTTASK` 363 See :term:`bitbake:BB_CURRENTTASK` in the BitBake manual. 364 365 :term:`BB_DANGLINGAPPENDS_WARNONLY` 366 Defines how BitBake handles situations where an append file 367 (``.bbappend``) has no corresponding recipe file (``.bb``). This 368 condition often occurs when layers get out of sync (e.g. ``oe-core`` 369 bumps a recipe version and the old recipe no longer exists and the 370 other layer has not been updated to the new version of the recipe 371 yet). 372 373 The default fatal behavior is safest because it is the sane reaction 374 given something is out of sync. It is important to realize when your 375 changes are no longer being applied. 376 377 You can change the default behavior by setting this variable to "1", 378 "yes", or "true" in your ``local.conf`` file, which is located in the 379 :term:`Build Directory`: Here is an example:: 380 381 BB_DANGLINGAPPENDS_WARNONLY = "1" 382 383 :term:`BB_DEFAULT_TASK` 384 See :term:`bitbake:BB_DEFAULT_TASK` in the BitBake manual. 385 386 :term:`BB_DEFAULT_UMASK` 387 See :term:`bitbake:BB_DEFAULT_UMASK` in the BitBake manual. 388 389 :term:`BB_DISKMON_DIRS` 390 Monitors disk space and available inodes during the build and allows 391 you to control the build based on these parameters. 392 393 Disk space monitoring is disabled by default. To enable monitoring, 394 add the :term:`BB_DISKMON_DIRS` variable to your ``conf/local.conf`` file 395 found in the :term:`Build Directory`. Use the 396 following form: 397 398 .. code-block:: none 399 400 BB_DISKMON_DIRS = "action,dir,threshold [...]" 401 402 where: 403 404 action is: 405 ABORT: Immediately stop the build when 406 a threshold is broken. 407 STOPTASKS: Stop the build after the currently 408 executing tasks have finished when 409 a threshold is broken. 410 WARN: Issue a warning but continue the 411 build when a threshold is broken. 412 Subsequent warnings are issued as 413 defined by the BB_DISKMON_WARNINTERVAL 414 variable, which must be defined in 415 the conf/local.conf file. 416 417 dir is: 418 Any directory you choose. You can specify one or 419 more directories to monitor by separating the 420 groupings with a space. If two directories are 421 on the same device, only the first directory 422 is monitored. 423 424 threshold is: 425 Either the minimum available disk space, 426 the minimum number of free inodes, or 427 both. You must specify at least one. To 428 omit one or the other, simply omit the value. 429 Specify the threshold using G, M, K for Gbytes, 430 Mbytes, and Kbytes, respectively. If you do 431 not specify G, M, or K, Kbytes is assumed by 432 default. Do not use GB, MB, or KB. 433 434 Here are some examples:: 435 436 BB_DISKMON_DIRS = "ABORT,${TMPDIR},1G,100K WARN,${SSTATE_DIR},1G,100K" 437 BB_DISKMON_DIRS = "STOPTASKS,${TMPDIR},1G" 438 BB_DISKMON_DIRS = "ABORT,${TMPDIR},,100K" 439 440 The first example works only if you also provide the 441 :term:`BB_DISKMON_WARNINTERVAL` 442 variable in the ``conf/local.conf``. This example causes the build 443 system to immediately stop when either the disk space in 444 ``${TMPDIR}`` drops below 1 Gbyte or the available free inodes drops 445 below 100 Kbytes. Because two directories are provided with the 446 variable, the build system also issue a warning when the disk space 447 in the ``${SSTATE_DIR}`` directory drops below 1 Gbyte or the number 448 of free inodes drops below 100 Kbytes. Subsequent warnings are issued 449 during intervals as defined by the :term:`BB_DISKMON_WARNINTERVAL` 450 variable. 451 452 The second example stops the build after all currently executing 453 tasks complete when the minimum disk space in the ``${TMPDIR}`` 454 directory drops below 1 Gbyte. No disk monitoring occurs for the free 455 inodes in this case. 456 457 The final example immediately stops the build when the number of 458 free inodes in the ``${TMPDIR}`` directory drops below 100 Kbytes. No 459 disk space monitoring for the directory itself occurs in this case. 460 461 :term:`BB_DISKMON_WARNINTERVAL` 462 Defines the disk space and free inode warning intervals. To set these 463 intervals, define the variable in your ``conf/local.conf`` file in 464 the :term:`Build Directory`. 465 466 If you are going to use the :term:`BB_DISKMON_WARNINTERVAL` variable, you 467 must also use the :term:`BB_DISKMON_DIRS` 468 variable and define its action as "WARN". During the build, 469 subsequent warnings are issued each time disk space or number of free 470 inodes further reduces by the respective interval. 471 472 If you do not provide a :term:`BB_DISKMON_WARNINTERVAL` variable and you 473 do use :term:`BB_DISKMON_DIRS` with the "WARN" action, the disk 474 monitoring interval defaults to the following:: 475 476 BB_DISKMON_WARNINTERVAL = "50M,5K" 477 478 When specifying the variable in your configuration file, use the 479 following form: 480 481 .. code-block:: none 482 483 BB_DISKMON_WARNINTERVAL = "disk_space_interval,disk_inode_interval" 484 485 where: 486 487 disk_space_interval is: 488 An interval of memory expressed in either 489 G, M, or K for Gbytes, Mbytes, or Kbytes, 490 respectively. You cannot use GB, MB, or KB. 491 492 disk_inode_interval is: 493 An interval of free inodes expressed in either 494 G, M, or K for Gbytes, Mbytes, or Kbytes, 495 respectively. You cannot use GB, MB, or KB. 496 497 Here is an example:: 498 499 BB_DISKMON_DIRS = "WARN,${SSTATE_DIR},1G,100K" 500 BB_DISKMON_WARNINTERVAL = "50M,5K" 501 502 These variables cause the 503 OpenEmbedded build system to issue subsequent warnings each time the 504 available disk space further reduces by 50 Mbytes or the number of 505 free inodes further reduces by 5 Kbytes in the ``${SSTATE_DIR}`` 506 directory. Subsequent warnings based on the interval occur each time 507 a respective interval is reached beyond the initial warning (i.e. 1 508 Gbytes and 100 Kbytes). 509 510 :term:`BB_ENV_PASSTHROUGH` 511 See :term:`bitbake:BB_ENV_PASSTHROUGH` in the BitBake manual. 512 513 :term:`BB_ENV_PASSTHROUGH_ADDITIONS` 514 See :term:`bitbake:BB_ENV_PASSTHROUGH_ADDITIONS` in the BitBake manual. 515 516 :term:`BB_FETCH_PREMIRRORONLY` 517 See :term:`bitbake:BB_FETCH_PREMIRRORONLY` in the BitBake manual. 518 519 :term:`BB_FILENAME` 520 See :term:`bitbake:BB_FILENAME` in the BitBake manual. 521 522 :term:`BB_GENERATE_MIRROR_TARBALLS` 523 Causes tarballs of the source control repositories (e.g. Git 524 repositories), including metadata, to be placed in the 525 :term:`DL_DIR` directory. 526 527 For performance reasons, creating and placing tarballs of these 528 repositories is not the default action by the OpenEmbedded build 529 system:: 530 531 BB_GENERATE_MIRROR_TARBALLS = "1" 532 533 Set this variable in your 534 ``local.conf`` file in the :term:`Build Directory`. 535 536 Once you have the tarballs containing your source files, you can 537 clean up your :term:`DL_DIR` directory by deleting any Git or other 538 source control work directories. 539 540 :term:`BB_GENERATE_SHALLOW_TARBALLS` 541 See :term:`bitbake:BB_GENERATE_SHALLOW_TARBALLS` in the BitBake manual. 542 543 :term:`BB_GIT_SHALLOW` 544 See :term:`bitbake:BB_GIT_SHALLOW` in the BitBake manual. 545 546 :term:`BB_GIT_SHALLOW_DEPTH` 547 See :term:`bitbake:BB_GIT_SHALLOW_DEPTH` in the BitBake manual. 548 549 :term:`BB_HASHCHECK_FUNCTION` 550 See :term:`bitbake:BB_HASHCHECK_FUNCTION` in the BitBake manual. 551 552 :term:`BB_HASHCONFIG_IGNORE_VARS` 553 See :term:`bitbake:BB_HASHCONFIG_IGNORE_VARS` in the BitBake manual. 554 555 :term:`BB_HASHSERVE` 556 See :term:`bitbake:BB_HASHSERVE` in the BitBake manual. 557 558 :term:`BB_HASHSERVE_UPSTREAM` 559 See :term:`bitbake:BB_HASHSERVE_UPSTREAM` in the BitBake manual. 560 561 :term:`BB_INVALIDCONF` 562 See :term:`bitbake:BB_INVALIDCONF` in the BitBake manual. 563 564 :term:`BB_LOGCONFIG` 565 See :term:`bitbake:BB_LOGCONFIG` in the BitBake manual. 566 567 :term:`BB_LOGFMT` 568 See :term:`bitbake:BB_LOGFMT` in the BitBake manual. 569 570 :term:`BB_MULTI_PROVIDER_ALLOWED` 571 See :term:`bitbake:BB_MULTI_PROVIDER_ALLOWED` in the BitBake manual. 572 573 :term:`BB_NICE_LEVEL` 574 See :term:`bitbake:BB_NICE_LEVEL` in the BitBake manual. 575 576 :term:`BB_NO_NETWORK` 577 See :term:`bitbake:BB_NO_NETWORK` in the BitBake manual. 578 579 :term:`BB_NUMBER_PARSE_THREADS` 580 See :term:`bitbake:BB_NUMBER_PARSE_THREADS` in the BitBake manual. 581 582 :term:`BB_NUMBER_THREADS` 583 The maximum number of tasks BitBake should run in parallel at any one 584 time. The OpenEmbedded build system automatically configures this 585 variable to be equal to the number of cores on the build system. For 586 example, a system with a dual core processor that also uses 587 hyper-threading causes the :term:`BB_NUMBER_THREADS` variable to default 588 to "4". 589 590 For single socket systems (i.e. one CPU), you should not have to 591 override this variable to gain optimal parallelism during builds. 592 However, if you have very large systems that employ multiple physical 593 CPUs, you might want to make sure the :term:`BB_NUMBER_THREADS` variable 594 is not set higher than "20". 595 596 For more information on speeding up builds, see the 597 ":ref:`dev-manual/speeding-up-build:speeding up a build`" 598 section in the Yocto Project Development Tasks Manual. 599 600 On the other hand, if your goal is to limit the amount of system 601 resources consumed by BitBake tasks, setting :term:`BB_NUMBER_THREADS` 602 to a number lower than the number of CPU threads in your machine 603 won't be sufficient. That's because each package will still be built 604 and installed through a number of parallel jobs specified by the 605 :term:`PARALLEL_MAKE` variable, which is by default the number of CPU 606 threads in your system, and is not impacted by the 607 :term:`BB_NUMBER_THREADS` value. 608 609 So, if you set :term:`BB_NUMBER_THREADS` to "1" but don't set 610 :term:`PARALLEL_MAKE`, most of your system resources will be consumed 611 anyway. 612 613 Therefore, if you intend to reduce the load of your build system by 614 setting :term:`BB_NUMBER_THREADS` to a relatively low value compared 615 to the number of CPU threads on your system, you should also set 616 :term:`PARALLEL_MAKE` to a similarly low value. 617 618 An alternative to using :term:`BB_NUMBER_THREADS` to keep the usage 619 of build system resources under control is to use the smarter 620 :term:`BB_PRESSURE_MAX_CPU`, :term:`BB_PRESSURE_MAX_IO` or 621 :term:`BB_PRESSURE_MAX_MEMORY` controls. They will prevent BitBake 622 from starting new tasks as long as thresholds are exceeded. Anyway, 623 as with :term:`BB_NUMBER_THREADS`, such controls won't prevent the 624 tasks already being run from using all CPU threads on the system 625 if :term:`PARALLEL_MAKE` is not set to a low value. 626 627 :term:`BB_ORIGENV` 628 See :term:`bitbake:BB_ORIGENV` in the BitBake manual. 629 630 :term:`BB_PRESERVE_ENV` 631 See :term:`bitbake:BB_PRESERVE_ENV` in the BitBake manual. 632 633 :term:`BB_PRESSURE_MAX_CPU` 634 See :term:`bitbake:BB_PRESSURE_MAX_CPU` in the BitBake manual. 635 636 :term:`BB_PRESSURE_MAX_IO` 637 See :term:`bitbake:BB_PRESSURE_MAX_IO` in the BitBake manual. 638 639 :term:`BB_PRESSURE_MAX_MEMORY` 640 See :term:`bitbake:BB_PRESSURE_MAX_MEMORY` in the BitBake manual. 641 642 :term:`BB_RUNFMT` 643 See :term:`bitbake:BB_RUNFMT` in the BitBake manual. 644 645 :term:`BB_RUNTASK` 646 See :term:`bitbake:BB_RUNTASK` in the BitBake manual. 647 648 :term:`BB_SCHEDULER` 649 See :term:`bitbake:BB_SCHEDULER` in the BitBake manual. 650 651 :term:`BB_SCHEDULERS` 652 See :term:`bitbake:BB_SCHEDULERS` in the BitBake manual. 653 654 :term:`BB_SERVER_TIMEOUT` 655 Specifies the time (in seconds) after which to unload the BitBake 656 server due to inactivity. Set :term:`BB_SERVER_TIMEOUT` to determine how 657 long the BitBake server stays resident between invocations. 658 659 For example, the following statement in your ``local.conf`` file 660 instructs the server to be unloaded after 20 seconds of inactivity:: 661 662 BB_SERVER_TIMEOUT = "20" 663 664 If you want the server to never be unloaded, 665 set :term:`BB_SERVER_TIMEOUT` to "-1". 666 667 :term:`BB_SETSCENE_DEPVALID` 668 See :term:`bitbake:BB_SETSCENE_DEPVALID` in the BitBake manual. 669 670 :term:`BB_SIGNATURE_EXCLUDE_FLAGS` 671 See :term:`bitbake:BB_SIGNATURE_EXCLUDE_FLAGS` in the BitBake manual. 672 673 :term:`BB_SIGNATURE_HANDLER` 674 See :term:`bitbake:BB_SIGNATURE_HANDLER` in the BitBake manual. 675 676 :term:`BB_SRCREV_POLICY` 677 See :term:`bitbake:BB_SRCREV_POLICY` in the BitBake manual. 678 679 :term:`BB_STRICT_CHECKSUM` 680 See :term:`bitbake:BB_STRICT_CHECKSUM` in the BitBake manual. 681 682 :term:`BB_TASK_IONICE_LEVEL` 683 See :term:`bitbake:BB_TASK_IONICE_LEVEL` in the BitBake manual. 684 685 :term:`BB_TASK_NICE_LEVEL` 686 See :term:`bitbake:BB_TASK_NICE_LEVEL` in the BitBake manual. 687 688 :term:`BB_TASKHASH` 689 See :term:`bitbake:BB_TASKHASH` in the BitBake manual. 690 691 :term:`BB_VERBOSE_LOGS` 692 See :term:`bitbake:BB_VERBOSE_LOGS` in the BitBake manual. 693 694 :term:`BB_WORKERCONTEXT` 695 See :term:`bitbake:BB_WORKERCONTEXT` in the BitBake manual. 696 697 :term:`BBCLASSEXTEND` 698 Allows you to extend a recipe so that it builds variants of the 699 software. There are common variants for recipes as "natives" like 700 ``quilt-native``, which is a copy of Quilt built to run on the build 701 system; "crosses" such as ``gcc-cross``, which is a compiler built to 702 run on the build machine but produces binaries that run on the target 703 :term:`MACHINE`; ":ref:`ref-classes-nativesdk`", which 704 targets the SDK machine instead of :term:`MACHINE`; and "mulitlibs" in 705 the form "``multilib:``\ multilib_name". 706 707 To build a different variant of the recipe with a minimal amount of 708 code, it usually is as simple as adding the following to your recipe:: 709 710 BBCLASSEXTEND =+ "native nativesdk" 711 BBCLASSEXTEND =+ "multilib:multilib_name" 712 713 .. note:: 714 715 Internally, the :term:`BBCLASSEXTEND` mechanism generates recipe 716 variants by rewriting variable values and applying overrides such 717 as ``:class-native``. For example, to generate a native version of 718 a recipe, a :term:`DEPENDS` on "foo" is rewritten 719 to a :term:`DEPENDS` on "foo-native". 720 721 Even when using :term:`BBCLASSEXTEND`, the recipe is only parsed once. 722 Parsing once adds some limitations. For example, it is not 723 possible to include a different file depending on the variant, 724 since ``include`` statements are processed when the recipe is 725 parsed. 726 727 :term:`BBDEBUG` 728 See :term:`bitbake:BBDEBUG` in the BitBake manual. 729 730 :term:`BBFILE_COLLECTIONS` 731 Lists the names of configured layers. These names are used to find 732 the other ``BBFILE_*`` variables. Typically, each layer will append 733 its name to this variable in its ``conf/layer.conf`` file. 734 735 :term:`BBFILE_PATTERN` 736 Variable that expands to match files from 737 :term:`BBFILES` in a particular layer. This variable 738 is used in the ``conf/layer.conf`` file and must be suffixed with the 739 name of the specific layer (e.g. ``BBFILE_PATTERN_emenlow``). 740 741 :term:`BBFILE_PRIORITY` 742 Assigns the priority for recipe files in each layer. 743 744 This variable is useful in situations where the same recipe appears 745 in more than one layer. Setting this variable allows you to 746 prioritize a layer against other layers that contain the same recipe 747 --- effectively letting you control the precedence for the multiple 748 layers. The precedence established through this variable stands 749 regardless of a recipe's version (:term:`PV` variable). For 750 example, a layer that has a recipe with a higher :term:`PV` value but for 751 which the :term:`BBFILE_PRIORITY` is set to have a lower precedence still 752 has a lower precedence. 753 754 A larger value for the :term:`BBFILE_PRIORITY` variable results in a 755 higher precedence. For example, the value 6 has a higher precedence 756 than the value 5. If not specified, the :term:`BBFILE_PRIORITY` variable 757 is set based on layer dependencies (see the :term:`LAYERDEPENDS` variable 758 for more information. The default priority, if unspecified for a 759 layer with no dependencies, is the lowest defined priority + 1 (or 1 760 if no priorities are defined). 761 762 .. tip:: 763 764 You can use the command ``bitbake-layers show-layers`` 765 to list all configured layers along with their priorities. 766 767 :term:`BBFILES` 768 A space-separated list of recipe files BitBake uses to build 769 software. 770 771 When specifying recipe files, you can pattern match using Python's 772 `glob <https://docs.python.org/3/library/glob.html>`__ syntax. 773 For details on the syntax, see the documentation by following the 774 previous link. 775 776 :term:`BBFILES_DYNAMIC` 777 Activates content when identified layers are present. You identify 778 the layers by the collections that the layers define. 779 780 Use the :term:`BBFILES_DYNAMIC` variable to avoid ``.bbappend`` files 781 whose corresponding ``.bb`` file is in a layer that attempts to 782 modify other layers through ``.bbappend`` but does not want to 783 introduce a hard dependency on those other layers. 784 785 Use the following form for :term:`BBFILES_DYNAMIC`: 786 ``collection_name:filename_pattern``. 787 788 The following example identifies two collection names and two 789 filename patterns:: 790 791 BBFILES_DYNAMIC += " \ 792 clang-layer:${LAYERDIR}/bbappends/meta-clang/*/*/*.bbappend \ 793 core:${LAYERDIR}/bbappends/openembedded-core/meta/*/*/*.bbappend \ 794 " 795 796 This next example shows an error message that occurs because invalid 797 entries are found, which cause parsing to fail: 798 799 .. code-block:: none 800 801 ERROR: BBFILES_DYNAMIC entries must be of the form <collection name>:<filename pattern>, not: 802 /work/my-layer/bbappends/meta-security-isafw/*/*/*.bbappend 803 /work/my-layer/bbappends/openembedded-core/meta/*/*/*.bbappend 804 805 :term:`BBINCLUDED` 806 See :term:`bitbake:BBINCLUDED` in the BitBake manual. 807 808 :term:`BBINCLUDELOGS` 809 Variable that controls how BitBake displays logs on build failure. 810 811 :term:`BBINCLUDELOGS_LINES` 812 If :term:`BBINCLUDELOGS` is set, specifies the 813 maximum number of lines from the task log file to print when 814 reporting a failed task. If you do not set :term:`BBINCLUDELOGS_LINES`, 815 the entire log is printed. 816 817 :term:`BBLAYERS` 818 Lists the layers to enable during the build. This variable is defined 819 in the ``bblayers.conf`` configuration file in the :term:`Build Directory`. 820 Here is an example:: 821 822 BBLAYERS = " \ 823 /home/scottrif/poky/meta \ 824 /home/scottrif/poky/meta-poky \ 825 /home/scottrif/poky/meta-yocto-bsp \ 826 /home/scottrif/poky/meta-mykernel \ 827 " 828 829 This example enables four layers, one of which is a custom, 830 user-defined layer named ``meta-mykernel``. 831 832 :term:`BBLAYERS_FETCH_DIR` 833 See :term:`bitbake:BBLAYERS_FETCH_DIR` in the BitBake manual. 834 835 :term:`BBMASK` 836 Prevents BitBake from processing recipes and recipe append files. 837 838 You can use the :term:`BBMASK` variable to "hide" these ``.bb`` and 839 ``.bbappend`` files. BitBake ignores any recipe or recipe append 840 files that match any of the expressions. It is as if BitBake does not 841 see them at all. Consequently, matching files are not parsed or 842 otherwise used by BitBake. 843 844 The values you provide are passed to Python's regular expression 845 compiler. Consequently, the syntax follows Python's Regular 846 Expression (re) syntax. The expressions are compared against the full 847 paths to the files. For complete syntax information, see Python's 848 documentation at https://docs.python.org/3/library/re.html#regular-expression-syntax. 849 850 The following example uses a complete regular expression to tell 851 BitBake to ignore all recipe and recipe append files in the 852 ``meta-ti/recipes-misc/`` directory:: 853 854 BBMASK = "meta-ti/recipes-misc/" 855 856 If you want to mask out multiple directories or recipes, you can 857 specify multiple regular expression fragments. This next example 858 masks out multiple directories and individual recipes:: 859 860 BBMASK += "/meta-ti/recipes-misc/ meta-ti/recipes-ti/packagegroup/" 861 BBMASK += "/meta-oe/recipes-support/" 862 BBMASK += "/meta-foo/.*/openldap" 863 BBMASK += "opencv.*\.bbappend" 864 BBMASK += "lzma" 865 866 .. note:: 867 868 When specifying a directory name, use the trailing slash character 869 to ensure you match just that directory name. 870 871 :term:`BBMULTICONFIG` 872 Specifies each additional separate configuration when you are 873 building targets with multiple configurations. Use this variable in 874 your ``conf/local.conf`` configuration file. Specify a 875 multiconfigname for each configuration file you are using. For 876 example, the following line specifies three configuration files:: 877 878 BBMULTICONFIG = "configA configB configC" 879 880 Each configuration file you use must reside in a ``multiconfig`` 881 subdirectory of a configuration directory within a layer, or 882 within the :term:`Build Directory` (e.g. 883 ``build_directory/conf/multiconfig/configA.conf`` or 884 ``mylayer/conf/multiconfig/configB.conf``). 885 886 For information on how to use :term:`BBMULTICONFIG` in an environment 887 that supports building targets with multiple configurations, see the 888 ":ref:`dev-manual/building:building images for multiple targets using multiple configurations`" 889 section in the Yocto Project Development Tasks Manual. 890 891 :term:`BBPATH` 892 See :term:`bitbake:BBPATH` in the BitBake manual. 893 894 :term:`BBSERVER` 895 If defined in the BitBake environment, :term:`BBSERVER` points to the 896 BitBake remote server. 897 898 Use the following format to export the variable to the BitBake 899 environment:: 900 901 export BBSERVER=localhost:$port 902 903 By default, :term:`BBSERVER` also appears in :term:`BB_BASEHASH_IGNORE_VARS`. 904 Consequently, :term:`BBSERVER` is excluded from checksum and dependency 905 data. 906 907 :term:`BBTARGETS` 908 See :term:`bitbake:BBTARGETS` in the BitBake manual. 909 910 :term:`BINCONFIG` 911 When inheriting the :ref:`ref-classes-binconfig-disabled` class, this 912 variable specifies binary configuration scripts to disable in favor of 913 using ``pkg-config`` to query the information. The 914 :ref:`ref-classes-binconfig-disabled` class will modify the specified 915 scripts to return an error so that calls to them can be easily found 916 and replaced. 917 918 To add multiple scripts, separate them by spaces. Here is an example 919 from the ``libpng`` recipe:: 920 921 BINCONFIG = "${bindir}/libpng-config ${bindir}/libpng16-config" 922 923 :term:`BINCONFIG_GLOB` 924 When inheriting the :ref:`ref-classes-binconfig` class, 925 this variable specifies a wildcard for configuration scripts that 926 need editing. The scripts are edited to correct any paths that have 927 been set up during compilation so that they are correct for use when 928 installed into the sysroot and called by the build processes of other 929 recipes. 930 931 .. note:: 932 933 The :term:`BINCONFIG_GLOB` variable uses 934 `shell globbing <https://tldp.org/LDP/abs/html/globbingref.html>`__, 935 which is recognition and expansion of wildcards during pattern 936 matching. Shell globbing is very similar to 937 `fnmatch <https://docs.python.org/3/library/fnmatch.html#module-fnmatch>`__ 938 and `glob <https://docs.python.org/3/library/glob.html>`__. 939 940 For more information on how this variable works, see 941 ``meta/classes-recipe/binconfig.bbclass`` in the :term:`Source Directory`. 942 You can also find general 943 information on the class in the 944 ":ref:`ref-classes-binconfig`" section. 945 946 :term:`BITBAKE_UI` 947 See :term:`bitbake:BITBAKE_UI` in the BitBake manual. 948 949 :term:`BP` 950 The base recipe name and version but without any special recipe name 951 suffix (i.e. ``-native``, ``lib64-``, and so forth). :term:`BP` is 952 comprised of the following:: 953 954 ${BPN}-${PV} 955 956 :term:`BPN` 957 This variable is a version of the :term:`PN` variable with 958 common prefixes and suffixes removed, such as ``nativesdk-``, 959 ``-cross``, ``-native``, and multilib's ``lib64-`` and ``lib32-``. 960 The exact lists of prefixes and suffixes removed are specified by the 961 :term:`MLPREFIX` and 962 :term:`SPECIAL_PKGSUFFIX` variables, 963 respectively. 964 965 :term:`BUGTRACKER` 966 Specifies a URL for an upstream bug tracking website for a recipe. 967 The OpenEmbedded build system does not use this variable. Rather, the 968 variable is a useful pointer in case a bug in the software being 969 built needs to be manually reported. 970 971 :term:`BUILD_ARCH` 972 Specifies the architecture of the build host (e.g. ``i686``). The 973 OpenEmbedded build system sets the value of :term:`BUILD_ARCH` from the 974 machine name reported by the ``uname`` command. 975 976 :term:`BUILD_AS_ARCH` 977 Specifies the architecture-specific assembler flags for the build 978 host. By default, the value of :term:`BUILD_AS_ARCH` is empty. 979 980 :term:`BUILD_CC_ARCH` 981 Specifies the architecture-specific C compiler flags for the build 982 host. By default, the value of :term:`BUILD_CC_ARCH` is empty. 983 984 :term:`BUILD_CCLD` 985 Specifies the linker command to be used for the build host when the C 986 compiler is being used as the linker. By default, :term:`BUILD_CCLD` 987 points to GCC and passes as arguments the value of 988 :term:`BUILD_CC_ARCH`, assuming 989 :term:`BUILD_CC_ARCH` is set. 990 991 :term:`BUILD_CFLAGS` 992 Specifies the flags to pass to the C compiler when building for the 993 build host. When building in the ``-native`` context, 994 :term:`CFLAGS` is set to the value of this variable by 995 default. 996 997 :term:`BUILD_CPPFLAGS` 998 Specifies the flags to pass to the C preprocessor (i.e. to both the C 999 and the C++ compilers) when building for the build host. When 1000 building in the ``-native`` context, :term:`CPPFLAGS` 1001 is set to the value of this variable by default. 1002 1003 :term:`BUILD_CXXFLAGS` 1004 Specifies the flags to pass to the C++ compiler when building for the 1005 build host. When building in the ``-native`` context, 1006 :term:`CXXFLAGS` is set to the value of this variable 1007 by default. 1008 1009 :term:`BUILD_FC` 1010 Specifies the Fortran compiler command for the build host. By 1011 default, :term:`BUILD_FC` points to Gfortran and passes as arguments the 1012 value of :term:`BUILD_CC_ARCH`, assuming 1013 :term:`BUILD_CC_ARCH` is set. 1014 1015 :term:`BUILD_LD` 1016 Specifies the linker command for the build host. By default, 1017 :term:`BUILD_LD` points to the GNU linker (ld) and passes as arguments 1018 the value of :term:`BUILD_LD_ARCH`, assuming 1019 :term:`BUILD_LD_ARCH` is set. 1020 1021 :term:`BUILD_LD_ARCH` 1022 Specifies architecture-specific linker flags for the build host. By 1023 default, the value of :term:`BUILD_LD_ARCH` is empty. 1024 1025 :term:`BUILD_LDFLAGS` 1026 Specifies the flags to pass to the linker when building for the build 1027 host. When building in the ``-native`` context, 1028 :term:`LDFLAGS` is set to the value of this variable 1029 by default. 1030 1031 :term:`BUILD_OPTIMIZATION` 1032 Specifies the optimization flags passed to the C compiler when 1033 building for the build host or the SDK. The flags are passed through 1034 the :term:`BUILD_CFLAGS` and 1035 :term:`BUILDSDK_CFLAGS` default values. 1036 1037 The default value of the :term:`BUILD_OPTIMIZATION` variable is "-O2 1038 -pipe". 1039 1040 :term:`BUILD_OS` 1041 Specifies the operating system in use on the build host (e.g. 1042 "linux"). The OpenEmbedded build system sets the value of 1043 :term:`BUILD_OS` from the OS reported by the ``uname`` command --- the 1044 first word, converted to lower-case characters. 1045 1046 :term:`BUILD_PREFIX` 1047 The toolchain binary prefix used for native recipes. The OpenEmbedded 1048 build system uses the :term:`BUILD_PREFIX` value to set the 1049 :term:`TARGET_PREFIX` when building for :ref:`ref-classes-native` recipes. 1050 1051 :term:`BUILD_STRIP` 1052 Specifies the command to be used to strip debugging symbols from 1053 binaries produced for the build host. By default, :term:`BUILD_STRIP` 1054 points to 1055 ``${``\ :term:`BUILD_PREFIX`\ ``}strip``. 1056 1057 :term:`BUILD_SYS` 1058 Specifies the system, including the architecture and the operating 1059 system, to use when building for the build host (i.e. when building 1060 :ref:`ref-classes-native` recipes). 1061 1062 The OpenEmbedded build system automatically sets this variable based 1063 on :term:`BUILD_ARCH`, 1064 :term:`BUILD_VENDOR`, and 1065 :term:`BUILD_OS`. You do not need to set the 1066 :term:`BUILD_SYS` variable yourself. 1067 1068 :term:`BUILD_VENDOR` 1069 Specifies the vendor name to use when building for the build host. 1070 The default value is an empty string (""). 1071 1072 :term:`BUILDDIR` 1073 Points to the location of the :term:`Build Directory`. You can define 1074 this directory indirectly through the :ref:`structure-core-script` script 1075 by passing in a :term:`Build Directory` path when you run the script. If 1076 you run the script and do not provide a :term:`Build Directory` path, the 1077 :term:`BUILDDIR` defaults to ``build`` in the current directory. 1078 1079 :term:`BUILDHISTORY_COMMIT` 1080 When inheriting the :ref:`ref-classes-buildhistory` class, this variable 1081 specifies whether or not to commit the build history output in a local 1082 Git repository. If set to "1", this local repository will be maintained 1083 automatically by the :ref:`ref-classes-buildhistory` class and a commit 1084 will be created on every build for changes to each top-level subdirectory 1085 of the build history output (images, packages, and sdk). If you want to 1086 track changes to build history over time, you should set this value to 1087 "1". 1088 1089 By default, the :ref:`ref-classes-buildhistory` class 1090 enables committing the buildhistory output in a local Git repository:: 1091 1092 BUILDHISTORY_COMMIT ?= "1" 1093 1094 :term:`BUILDHISTORY_COMMIT_AUTHOR` 1095 When inheriting the :ref:`ref-classes-buildhistory` 1096 class, this variable specifies the author to use for each Git commit. 1097 In order for the :term:`BUILDHISTORY_COMMIT_AUTHOR` variable to work, the 1098 :term:`BUILDHISTORY_COMMIT` variable must 1099 be set to "1". 1100 1101 Git requires that the value you provide for the 1102 :term:`BUILDHISTORY_COMMIT_AUTHOR` variable takes the form of "name 1103 email@host". Providing an email address or host that is not valid 1104 does not produce an error. 1105 1106 By default, the :ref:`ref-classes-buildhistory` class sets the variable 1107 as follows:: 1108 1109 BUILDHISTORY_COMMIT_AUTHOR ?= "buildhistory <buildhistory@${DISTRO}>" 1110 1111 :term:`BUILDHISTORY_DIR` 1112 When inheriting the :ref:`ref-classes-buildhistory` 1113 class, this variable specifies the directory in which build history 1114 information is kept. For more information on how the variable works, 1115 see the :ref:`ref-classes-buildhistory` class. 1116 1117 By default, the :ref:`ref-classes-buildhistory` class sets the directory 1118 as follows:: 1119 1120 BUILDHISTORY_DIR ?= "${TOPDIR}/buildhistory" 1121 1122 :term:`BUILDHISTORY_FEATURES` 1123 When inheriting the :ref:`ref-classes-buildhistory` 1124 class, this variable specifies the build history features to be 1125 enabled. For more information on how build history works, see the 1126 ":ref:`dev-manual/build-quality:maintaining build output quality`" 1127 section in the Yocto Project Development Tasks Manual. 1128 1129 You can specify these features in the form of a space-separated list: 1130 1131 - *image:* Analysis of the contents of images, which includes the 1132 list of installed packages among other things. 1133 1134 - *package:* Analysis of the contents of individual packages. 1135 1136 - *sdk:* Analysis of the contents of the software development kit 1137 (SDK). 1138 1139 - *task:* Save output file signatures for 1140 :ref:`shared state <overview-manual/concepts:shared state cache>` 1141 (sstate) tasks. 1142 This saves one file per task and lists the SHA-256 checksums for 1143 each file staged (i.e. the output of the task). 1144 1145 By default, the :ref:`ref-classes-buildhistory` class enables the 1146 following features:: 1147 1148 BUILDHISTORY_FEATURES ?= "image package sdk" 1149 1150 :term:`BUILDHISTORY_IMAGE_FILES` 1151 When inheriting the :ref:`ref-classes-buildhistory` 1152 class, this variable specifies a list of paths to files copied from 1153 the image contents into the build history directory under an 1154 "image-files" directory in the directory for the image, so that you 1155 can track the contents of each file. The default is to copy 1156 ``/etc/passwd`` and ``/etc/group``, which allows you to monitor for 1157 changes in user and group entries. You can modify the list to include 1158 any file. Specifying an invalid path does not produce an error. 1159 Consequently, you can include files that might not always be present. 1160 1161 By default, the :ref:`ref-classes-buildhistory` class provides paths to 1162 the following files:: 1163 1164 BUILDHISTORY_IMAGE_FILES ?= "/etc/passwd /etc/group" 1165 1166 :term:`BUILDHISTORY_PATH_PREFIX_STRIP` 1167 When inheriting the :ref:`ref-classes-buildhistory` 1168 class, this variable specifies a common path prefix that should be 1169 stripped off the beginning of paths in the task signature list when the 1170 ``task`` feature is active in :term:`BUILDHISTORY_FEATURES`. This can be 1171 useful when build history is populated from multiple sources that may not 1172 all use the same top level directory. 1173 1174 By default, the :ref:`ref-classes-buildhistory` class sets the variable 1175 as follows:: 1176 1177 BUILDHISTORY_PATH_PREFIX_STRIP ?= "" 1178 1179 In this case, no prefixes will be stripped. 1180 1181 :term:`BUILDHISTORY_PUSH_REPO` 1182 When inheriting the :ref:`ref-classes-buildhistory` class, this variable 1183 optionally specifies a remote repository to which build history pushes 1184 Git changes. In order for :term:`BUILDHISTORY_PUSH_REPO` to work, 1185 :term:`BUILDHISTORY_COMMIT` must be set to "1". 1186 1187 The repository should correspond to a remote address that specifies a 1188 repository as understood by Git, or alternatively to a remote name 1189 that you have set up manually using ``git remote`` within the local 1190 repository. 1191 1192 By default, the :ref:`ref-classes-buildhistory` class sets the variable 1193 as follows:: 1194 1195 BUILDHISTORY_PUSH_REPO ?= "" 1196 1197 :term:`BUILDNAME` 1198 See :term:`bitbake:BUILDNAME` in the BitBake manual. 1199 1200 :term:`BUILDSDK_CFLAGS` 1201 Specifies the flags to pass to the C compiler when building for the 1202 SDK. When building in the ``nativesdk-`` context, 1203 :term:`CFLAGS` is set to the value of this variable by 1204 default. 1205 1206 :term:`BUILDSDK_CPPFLAGS` 1207 Specifies the flags to pass to the C pre-processor (i.e. to both the 1208 C and the C++ compilers) when building for the SDK. When building in 1209 the ``nativesdk-`` context, :term:`CPPFLAGS` is set 1210 to the value of this variable by default. 1211 1212 :term:`BUILDSDK_CXXFLAGS` 1213 Specifies the flags to pass to the C++ compiler when building for the 1214 SDK. When building in the ``nativesdk-`` context, 1215 :term:`CXXFLAGS` is set to the value of this variable 1216 by default. 1217 1218 :term:`BUILDSDK_LDFLAGS` 1219 Specifies the flags to pass to the linker when building for the SDK. 1220 When building in the ``nativesdk-`` context, 1221 :term:`LDFLAGS` is set to the value of this variable 1222 by default. 1223 1224 :term:`BUILDSTATS_BASE` 1225 Points to the location of the directory that holds build statistics 1226 when you use and enable the :ref:`ref-classes-buildstats` class. The 1227 :term:`BUILDSTATS_BASE` directory defaults to 1228 ``${``\ :term:`TMPDIR`\ ``}/buildstats/``. 1229 1230 :term:`BUSYBOX_SPLIT_SUID` 1231 For the BusyBox recipe, specifies whether to split the output 1232 executable file into two parts: one for features that require 1233 ``setuid root``, and one for the remaining features (i.e. those that 1234 do not require ``setuid root``). 1235 1236 The :term:`BUSYBOX_SPLIT_SUID` variable defaults to "1", which results in 1237 splitting the output executable file. Set the variable to "0" to get 1238 a single output executable file. 1239 1240 :term:`BZRDIR` 1241 See :term:`bitbake:BZRDIR` in the BitBake manual. 1242 1243 :term:`CACHE` 1244 Specifies the directory BitBake uses to store a cache of the 1245 :term:`Metadata` so it does not need to be parsed every time 1246 BitBake is started. 1247 1248 :term:`CC` 1249 The minimal command and arguments used to run the C compiler. 1250 1251 :term:`CFLAGS` 1252 Specifies the flags to pass to the C compiler. This variable is 1253 exported to an environment variable and thus made visible to the 1254 software being built during the compilation step. 1255 1256 Default initialization for :term:`CFLAGS` varies depending on what is 1257 being built: 1258 1259 - :term:`TARGET_CFLAGS` when building for the 1260 target 1261 1262 - :term:`BUILD_CFLAGS` when building for the 1263 build host (i.e. ``-native``) 1264 1265 - :term:`BUILDSDK_CFLAGS` when building for 1266 an SDK (i.e. ``nativesdk-``) 1267 1268 :term:`CLASSOVERRIDE` 1269 An internal variable specifying the special class override that 1270 should currently apply (e.g. "class-target", "class-native", and so 1271 forth). The classes that use this variable (e.g. 1272 :ref:`ref-classes-native`, :ref:`ref-classes-nativesdk`, and so forth) 1273 set the variable to appropriate values. 1274 1275 .. note:: 1276 1277 :term:`CLASSOVERRIDE` gets its default "class-target" value from the 1278 ``bitbake.conf`` file. 1279 1280 As an example, the following override allows you to install extra 1281 files, but only when building for the target:: 1282 1283 do_install:append:class-target() { 1284 install my-extra-file ${D}${sysconfdir} 1285 } 1286 1287 Here is an example where ``FOO`` is set to 1288 "native" when building for the build host, and to "other" when not 1289 building for the build host:: 1290 1291 FOO:class-native = "native" 1292 FOO = "other" 1293 1294 The underlying mechanism behind :term:`CLASSOVERRIDE` is simply 1295 that it is included in the default value of 1296 :term:`OVERRIDES`. 1297 1298 :term:`CLEANBROKEN` 1299 If set to "1" within a recipe, :term:`CLEANBROKEN` specifies that the 1300 ``make clean`` command does not work for the software being built. 1301 Consequently, the OpenEmbedded build system will not try to run 1302 ``make clean`` during the :ref:`ref-tasks-configure` 1303 task, which is the default behavior. 1304 1305 :term:`COMBINED_FEATURES` 1306 Provides a list of hardware features that are enabled in both 1307 :term:`MACHINE_FEATURES` and 1308 :term:`DISTRO_FEATURES`. This select list of 1309 features contains features that make sense to be controlled both at 1310 the machine and distribution configuration level. For example, the 1311 "bluetooth" feature requires hardware support but should also be 1312 optional at the distribution level, in case the hardware supports 1313 Bluetooth but you do not ever intend to use it. 1314 1315 :term:`COMMERCIAL_AUDIO_PLUGINS` 1316 This variable is specific to the :yocto_git:`GStreamer recipes 1317 </poky/tree/meta/recipes-multimedia/gstreamer/gstreamer1.0-meta-base.bb>`. 1318 It allows to build the GStreamer `"ugly" 1319 <https://github.com/GStreamer/gst-plugins-ugly>`__ and 1320 `"bad" <https://github.com/GStreamer/gst-plugins-bad>`__ audio plugins. 1321 1322 See the :ref:`dev-manual/licenses:other variables related to commercial licenses` 1323 section for usage details. 1324 1325 :term:`COMMERCIAL_VIDEO_PLUGINS` 1326 This variable is specific to the :yocto_git:`GStreamer recipes 1327 </poky/tree/meta/recipes-multimedia/gstreamer/gstreamer1.0-meta-base.bb>`. 1328 It allows to build the GStreamer `"ugly" 1329 <https://github.com/GStreamer/gst-plugins-ugly>`__ and 1330 `"bad" <https://github.com/GStreamer/gst-plugins-bad>`__ video plugins. 1331 1332 See the :ref:`dev-manual/licenses:other variables related to commercial licenses` 1333 section for usage details. 1334 1335 :term:`COMMON_LICENSE_DIR` 1336 Points to ``meta/files/common-licenses`` in the 1337 :term:`Source Directory`, which is where generic license 1338 files reside. 1339 1340 :term:`COMPATIBLE_HOST` 1341 A regular expression that resolves to one or more hosts (when the 1342 recipe is native) or one or more targets (when the recipe is 1343 non-native) with which a recipe is compatible. The regular expression 1344 is matched against :term:`HOST_SYS`. You can use the 1345 variable to stop recipes from being built for classes of systems with 1346 which the recipes are not compatible. Stopping these builds is 1347 particularly useful with kernels. The variable also helps to increase 1348 parsing speed since the build system skips parsing recipes not 1349 compatible with the current system. 1350 1351 :term:`COMPATIBLE_MACHINE` 1352 A regular expression that resolves to one or more target machines 1353 with which a recipe is compatible. The regular expression is matched 1354 against :term:`MACHINEOVERRIDES`. You can use 1355 the variable to stop recipes from being built for machines with which 1356 the recipes are not compatible. Stopping these builds is particularly 1357 useful with kernels. The variable also helps to increase parsing 1358 speed since the build system skips parsing recipes not compatible 1359 with the current machine. 1360 1361 :term:`COMPLEMENTARY_GLOB` 1362 Defines wildcards to match when installing a list of complementary 1363 packages for all the packages explicitly (or implicitly) installed in 1364 an image. 1365 1366 The :term:`COMPLEMENTARY_GLOB` variable uses Unix filename pattern matching 1367 (`fnmatch <https://docs.python.org/3/library/fnmatch.html#module-fnmatch>`__), 1368 which is similar to the Unix style pathname pattern expansion 1369 (`glob <https://docs.python.org/3/library/glob.html>`__). 1370 1371 The resulting list of complementary packages is associated with an 1372 item that can be added to 1373 :term:`IMAGE_FEATURES`. An example usage of 1374 this is the "dev-pkgs" item that when added to :term:`IMAGE_FEATURES` 1375 will install -dev packages (containing headers and other development 1376 files) for every package in the image. 1377 1378 To add a new feature item pointing to a wildcard, use a variable flag 1379 to specify the feature item name and use the value to specify the 1380 wildcard. Here is an example:: 1381 1382 COMPLEMENTARY_GLOB[dev-pkgs] = '*-dev' 1383 1384 .. note:: 1385 1386 When installing complementary packages, recommends relationships 1387 (set via :term:`RRECOMMENDS`) are always ignored. 1388 1389 :term:`COMPONENTS_DIR` 1390 Stores sysroot components for each recipe. The OpenEmbedded build 1391 system uses :term:`COMPONENTS_DIR` when constructing recipe-specific 1392 sysroots for other recipes. 1393 1394 The default is 1395 "``${``\ :term:`STAGING_DIR`\ ``}-components``." 1396 (i.e. 1397 "``${``\ :term:`TMPDIR`\ ``}/sysroots-components``"). 1398 1399 :term:`CONF_VERSION` 1400 Tracks the version of the local configuration file (i.e. 1401 ``local.conf``). The value for :term:`CONF_VERSION` increments each time 1402 ``build/conf/`` compatibility changes. 1403 1404 :term:`CONFFILES` 1405 Identifies editable or configurable files that are part of a package. 1406 If the Package Management System (PMS) is being used to update 1407 packages on the target system, it is possible that configuration 1408 files you have changed after the original installation and that you 1409 now want to remain unchanged are overwritten. In other words, 1410 editable files might exist in the package that you do not want reset 1411 as part of the package update process. You can use the :term:`CONFFILES` 1412 variable to list the files in the package that you wish to prevent 1413 the PMS from overwriting during this update process. 1414 1415 To use the :term:`CONFFILES` variable, provide a package name override 1416 that identifies the resulting package. Then, provide a 1417 space-separated list of files. Here is an example:: 1418 1419 CONFFILES:${PN} += "${sysconfdir}/file1 \ 1420 ${sysconfdir}/file2 ${sysconfdir}/file3" 1421 1422 There is a relationship between the :term:`CONFFILES` and :term:`FILES` 1423 variables. The files listed within :term:`CONFFILES` must be a subset of 1424 the files listed within :term:`FILES`. Because the configuration files 1425 you provide with :term:`CONFFILES` are simply being identified so that 1426 the PMS will not overwrite them, it makes sense that the files must 1427 already be included as part of the package through the :term:`FILES` 1428 variable. 1429 1430 .. note:: 1431 1432 When specifying paths as part of the :term:`CONFFILES` variable, it is 1433 good practice to use appropriate path variables. 1434 For example, ``${sysconfdir}`` rather than ``/etc`` or ``${bindir}`` 1435 rather than ``/usr/bin``. You can find a list of these variables at 1436 the top of the ``meta/conf/bitbake.conf`` file in the 1437 :term:`Source Directory`. 1438 1439 :term:`CONFIG_INITRAMFS_SOURCE` 1440 Identifies the initial RAM filesystem (:term:`Initramfs`) source files. The 1441 OpenEmbedded build system receives and uses this kernel Kconfig 1442 variable as an environment variable. By default, the variable is set 1443 to null (""). 1444 1445 The :term:`CONFIG_INITRAMFS_SOURCE` can be either a single cpio archive 1446 with a ``.cpio`` suffix or a space-separated list of directories and 1447 files for building the :term:`Initramfs` image. A cpio archive should contain 1448 a filesystem archive to be used as an :term:`Initramfs` image. Directories 1449 should contain a filesystem layout to be included in the :term:`Initramfs` 1450 image. Files should contain entries according to the format described 1451 by the ``usr/gen_init_cpio`` program in the kernel tree. 1452 1453 If you specify multiple directories and files, the :term:`Initramfs` image 1454 will be the aggregate of all of them. 1455 1456 For information on creating an :term:`Initramfs`, see the 1457 ":ref:`dev-manual/building:building an initial ram filesystem (Initramfs) image`" section 1458 in the Yocto Project Development Tasks Manual. 1459 1460 :term:`CONFIG_SITE` 1461 A list of files that contains ``autoconf`` test results relevant to 1462 the current build. This variable is used by the Autotools utilities 1463 when running ``configure``. 1464 1465 :term:`CONFIGURE_FLAGS` 1466 The minimal arguments for GNU configure. 1467 1468 :term:`CONFLICT_DISTRO_FEATURES` 1469 When inheriting the :ref:`ref-classes-features_check` 1470 class, this variable identifies distribution features that would be 1471 in conflict should the recipe be built. In other words, if the 1472 :term:`CONFLICT_DISTRO_FEATURES` variable lists a feature that also 1473 appears in :term:`DISTRO_FEATURES` within the current configuration, then 1474 the recipe will be skipped, and if the build system attempts to build 1475 the recipe then an error will be triggered. 1476 1477 :term:`CONVERSION_CMD` 1478 This variable is used for storing image conversion commands. 1479 Image conversion can convert an image into different objects like: 1480 1481 - Compressed version of the image 1482 1483 - Checksums for the image 1484 1485 An example of :term:`CONVERSION_CMD` from :ref:`ref-classes-image_types` 1486 class is:: 1487 1488 CONVERSION_CMD:lzo = "lzop -9 ${IMAGE_NAME}${IMAGE_NAME_SUFFIX}.${type}" 1489 1490 :term:`COPY_LIC_DIRS` 1491 If set to "1" along with the 1492 :term:`COPY_LIC_MANIFEST` variable, the 1493 OpenEmbedded build system copies into the image the license files, 1494 which are located in ``/usr/share/common-licenses``, for each 1495 package. The license files are placed in directories within the image 1496 itself during build time. 1497 1498 .. note:: 1499 1500 The :term:`COPY_LIC_DIRS` does not offer a path for adding licenses for 1501 newly installed packages to an image, which might be most suitable for 1502 read-only filesystems that cannot be upgraded. See the 1503 :term:`LICENSE_CREATE_PACKAGE` variable for additional information. 1504 You can also reference the ":ref:`dev-manual/licenses:providing license text`" 1505 section in the Yocto Project Development Tasks Manual for 1506 information on providing license text. 1507 1508 :term:`COPY_LIC_MANIFEST` 1509 If set to "1", the OpenEmbedded build system copies the license 1510 manifest for the image to 1511 ``/usr/share/common-licenses/license.manifest`` within the image 1512 itself during build time. 1513 1514 .. note:: 1515 1516 The :term:`COPY_LIC_MANIFEST` does not offer a path for adding licenses for 1517 newly installed packages to an image, which might be most suitable for 1518 read-only filesystems that cannot be upgraded. See the 1519 :term:`LICENSE_CREATE_PACKAGE` variable for additional information. 1520 You can also reference the ":ref:`dev-manual/licenses:providing license text`" 1521 section in the Yocto Project Development Tasks Manual for 1522 information on providing license text. 1523 1524 :term:`COPYLEFT_LICENSE_EXCLUDE` 1525 A space-separated list of licenses to exclude from the source archived by 1526 the :ref:`ref-classes-archiver` class. In other words, if a license in a 1527 recipe's :term:`LICENSE` value is in the value of 1528 :term:`COPYLEFT_LICENSE_EXCLUDE`, then its source is not archived by the 1529 class. 1530 1531 .. note:: 1532 1533 The :term:`COPYLEFT_LICENSE_EXCLUDE` variable takes precedence over the 1534 :term:`COPYLEFT_LICENSE_INCLUDE` variable. 1535 1536 The default value, which is "CLOSED Proprietary", for 1537 :term:`COPYLEFT_LICENSE_EXCLUDE` is set by the 1538 :ref:`ref-classes-copyleft_filter` class, which 1539 is inherited by the :ref:`ref-classes-archiver` class. 1540 1541 :term:`COPYLEFT_LICENSE_INCLUDE` 1542 A space-separated list of licenses to include in the source archived 1543 by the :ref:`ref-classes-archiver` class. In other 1544 words, if a license in a recipe's :term:`LICENSE` 1545 value is in the value of :term:`COPYLEFT_LICENSE_INCLUDE`, then its 1546 source is archived by the class. 1547 1548 The default value is set by the :ref:`ref-classes-copyleft_filter` class, 1549 which is inherited by the :ref:`ref-classes-archiver` class. The default 1550 value includes "GPL*", "LGPL*", and "AGPL*". 1551 1552 :term:`COPYLEFT_PN_EXCLUDE` 1553 A list of recipes to exclude in the source archived by the 1554 :ref:`ref-classes-archiver` class. The :term:`COPYLEFT_PN_EXCLUDE` 1555 variable overrides the license inclusion and exclusion caused through the 1556 :term:`COPYLEFT_LICENSE_INCLUDE` and :term:`COPYLEFT_LICENSE_EXCLUDE` 1557 variables, respectively. 1558 1559 The default value, which is "" indicating to not explicitly exclude 1560 any recipes by name, for :term:`COPYLEFT_PN_EXCLUDE` is set by the 1561 :ref:`ref-classes-copyleft_filter` class, which is inherited by the 1562 :ref:`ref-classes-archiver` class. 1563 1564 :term:`COPYLEFT_PN_INCLUDE` 1565 A list of recipes to include in the source archived by the 1566 :ref:`ref-classes-archiver` class. The :term:`COPYLEFT_PN_INCLUDE` 1567 variable overrides the license inclusion and exclusion caused through the 1568 :term:`COPYLEFT_LICENSE_INCLUDE` and :term:`COPYLEFT_LICENSE_EXCLUDE` 1569 variables, respectively. 1570 1571 The default value, which is "" indicating to not explicitly include 1572 any recipes by name, for :term:`COPYLEFT_PN_INCLUDE` is set by the 1573 :ref:`ref-classes-copyleft_filter` class, which is inherited by the 1574 :ref:`ref-classes-archiver` class. 1575 1576 :term:`COPYLEFT_RECIPE_TYPES` 1577 A space-separated list of recipe types to include in the source 1578 archived by the :ref:`archiver <ref-classes-archiver>` class. 1579 Recipe types are ``target``, :ref:`ref-classes-native`, 1580 :ref:`ref-classes-nativesdk`, :ref:`ref-classes-cross`, 1581 :ref:`ref-classes-crosssdk`, and :ref:`ref-classes-cross-canadian`. 1582 1583 The default value, which is "target*", for :term:`COPYLEFT_RECIPE_TYPES` 1584 is set by the :ref:`ref-classes-copyleft_filter` class, which is 1585 inherited by the :ref:`ref-classes-archiver` class. 1586 1587 :term:`CORE_IMAGE_EXTRA_INSTALL` 1588 Specifies the list of packages to be added to the image. You should 1589 only set this variable in the ``local.conf`` configuration file found 1590 in the :term:`Build Directory`. 1591 1592 This variable replaces ``POKY_EXTRA_INSTALL``, which is no longer 1593 supported. 1594 1595 :term:`COREBASE` 1596 Specifies the parent directory of the OpenEmbedded-Core Metadata 1597 layer (i.e. ``meta``). 1598 1599 It is an important distinction that :term:`COREBASE` points to the parent 1600 of this layer and not the layer itself. Consider an example where you 1601 have cloned the Poky Git repository and retained the ``poky`` name 1602 for your local copy of the repository. In this case, :term:`COREBASE` 1603 points to the ``poky`` folder because it is the parent directory of 1604 the ``poky/meta`` layer. 1605 1606 :term:`COREBASE_FILES` 1607 Lists files from the :term:`COREBASE` directory that 1608 should be copied other than the layers listed in the 1609 ``bblayers.conf`` file. The :term:`COREBASE_FILES` variable allows 1610 to copy metadata from the OpenEmbedded build system 1611 into the extensible SDK. 1612 1613 Explicitly listing files in :term:`COREBASE` is needed because it 1614 typically contains build directories and other files that should not 1615 normally be copied into the extensible SDK. Consequently, the value 1616 of :term:`COREBASE_FILES` is used in order to only copy the files that 1617 are actually needed. 1618 1619 :term:`CPP` 1620 The minimal command and arguments used to run the C preprocessor. 1621 1622 :term:`CPPFLAGS` 1623 Specifies the flags to pass to the C pre-processor (i.e. to both the 1624 C and the C++ compilers). This variable is exported to an environment 1625 variable and thus made visible to the software being built during the 1626 compilation step. 1627 1628 Default initialization for :term:`CPPFLAGS` varies depending on what is 1629 being built: 1630 1631 - :term:`TARGET_CPPFLAGS` when building for 1632 the target 1633 1634 - :term:`BUILD_CPPFLAGS` when building for the 1635 build host (i.e. ``-native``) 1636 1637 - :term:`BUILDSDK_CPPFLAGS` when building 1638 for an SDK (i.e. ``nativesdk-``) 1639 1640 :term:`CROSS_COMPILE` 1641 The toolchain binary prefix for the target tools. The 1642 :term:`CROSS_COMPILE` variable is the same as the 1643 :term:`TARGET_PREFIX` variable. 1644 1645 .. note:: 1646 1647 The OpenEmbedded build system sets the :term:`CROSS_COMPILE` 1648 variable only in certain contexts (e.g. when building for kernel 1649 and kernel module recipes). 1650 1651 :term:`CVE_CHECK_IGNORE` 1652 This variable is deprecated and should be replaced by :term:`CVE_STATUS`. 1653 1654 :term:`CVE_CHECK_SHOW_WARNINGS` 1655 Specifies whether or not the :ref:`ref-classes-cve-check` 1656 class should generate warning messages on the console when unpatched 1657 CVEs are found. The default is "1", but you may wish to set it to "0" if 1658 you are already examining/processing the logs after the build has 1659 completed and thus do not need the warning messages. 1660 1661 :term:`CVE_CHECK_SKIP_RECIPE` 1662 The list of package names (:term:`PN`) for which 1663 CVEs (Common Vulnerabilities and Exposures) are ignored. 1664 1665 :term:`CVE_DB_UPDATE_INTERVAL` 1666 Specifies the CVE database update interval in seconds, as used by 1667 ``cve-update-db-native``. The default value is "86400" i.e. once a day 1668 (24*60*60). If the value is set to "0" then the update will be forced 1669 every time. Alternatively, a negative value e.g. "-1" will disable 1670 updates entirely. 1671 1672 :term:`CVE_PRODUCT` 1673 In a recipe, defines the name used to match the recipe name 1674 against the name in the upstream `NIST CVE database <https://nvd.nist.gov/>`__. 1675 1676 The default is ${:term:`BPN`} (except for recipes that inherit the 1677 :ref:`ref-classes-pypi` class where it is set based upon 1678 :term:`PYPI_PACKAGE`). If it does not match the name in the NIST CVE 1679 database or matches with multiple entries in the database, the default 1680 value needs to be changed. 1681 1682 Here is an example from the :oe_layerindex:`Berkeley DB recipe </layerindex/recipe/544>`:: 1683 1684 CVE_PRODUCT = "oracle_berkeley_db berkeley_db" 1685 1686 Sometimes the product name is not specific enough, for example 1687 "tar" has been matching CVEs for the GNU ``tar`` package and also 1688 the ``node-tar`` node.js extension. To avoid this problem, use the 1689 vendor name as a prefix. The syntax for this is:: 1690 1691 CVE_PRODUCT = "vendor:package" 1692 1693 :term:`CVE_STATUS` 1694 The CVE ID which is patched or should be ignored. Here is 1695 an example from the :oe_layerindex:`Python3 recipe</layerindex/recipe/23823>`:: 1696 1697 CVE_STATUS[CVE-2020-15523] = "not-applicable-platform: Issue only applies on Windows" 1698 1699 It has the format "reason: description" and the description is optional. 1700 The Reason is mapped to the final CVE state by mapping via 1701 :term:`CVE_CHECK_STATUSMAP` 1702 1703 :term:`CVE_STATUS_GROUPS` 1704 If there are many CVEs with the same status and reason, they can by simplified by using this 1705 variable instead of many similar lines with :term:`CVE_STATUS`:: 1706 1707 CVE_STATUS_GROUPS = "CVE_STATUS_WIN CVE_STATUS_PATCHED" 1708 1709 CVE_STATUS_WIN = "CVE-1234-0001 CVE-1234-0002" 1710 CVE_STATUS_WIN[status] = "not-applicable-platform: Issue only applies on Windows" 1711 CVE_STATUS_PATCHED = "CVE-1234-0003 CVE-1234-0004" 1712 CVE_STATUS_PATCHED[status] = "fixed-version: Fixed externally" 1713 1714 :term:`CVE_CHECK_STATUSMAP` 1715 Mapping variable for all possible reasons of :term:`CVE_STATUS`: 1716 ``Patched``, ``Unpatched`` and ``Ignored``. 1717 See :ref:`ref-classes-cve-check` or ``meta/conf/cve-check-map.conf`` for more details:: 1718 1719 CVE_CHECK_STATUSMAP[cpe-incorrect] = "Ignored" 1720 1721 :term:`CVE_VERSION` 1722 In a recipe, defines the version used to match the recipe version 1723 against the version in the `NIST CVE database <https://nvd.nist.gov/>`__ 1724 when usign :ref:`ref-classes-cve-check`. 1725 1726 The default is ${:term:`PV`} but if recipes use custom version numbers 1727 which do not map to upstream software component release versions and the versions 1728 used in the CVE database, then this variable can be used to set the 1729 version number for :ref:`ref-classes-cve-check`. Example:: 1730 1731 CVE_VERSION = "2.39" 1732 1733 :term:`CVSDIR` 1734 The directory in which files checked out under the CVS system are 1735 stored. 1736 1737 :term:`CXX` 1738 The minimal command and arguments used to run the C++ compiler. 1739 1740 :term:`CXXFLAGS` 1741 Specifies the flags to pass to the C++ compiler. This variable is 1742 exported to an environment variable and thus made visible to the 1743 software being built during the compilation step. 1744 1745 Default initialization for :term:`CXXFLAGS` varies depending on what is 1746 being built: 1747 1748 - :term:`TARGET_CXXFLAGS` when building for 1749 the target 1750 1751 - :term:`BUILD_CXXFLAGS` when building for the 1752 build host (i.e. ``-native``) 1753 1754 - :term:`BUILDSDK_CXXFLAGS` when building 1755 for an SDK (i.e. ``nativesdk-``) 1756 1757 :term:`D` 1758 The destination directory. The location in the :term:`Build Directory` 1759 where components are installed by the 1760 :ref:`ref-tasks-install` task. This location defaults 1761 to:: 1762 1763 ${WORKDIR}/image 1764 1765 .. note:: 1766 1767 Tasks that read from or write to this directory should run under 1768 :ref:`fakeroot <overview-manual/concepts:fakeroot and pseudo>`. 1769 1770 :term:`DATE` 1771 The date the build was started. Dates appear using the year, month, 1772 and day (YMD) format (e.g. "20150209" for February 9th, 2015). 1773 1774 :term:`DATETIME` 1775 The date and time on which the current build started. The format is 1776 suitable for timestamps. 1777 1778 :term:`DEBIAN_NOAUTONAME` 1779 When the :ref:`ref-classes-debian` class is inherited, 1780 which is the default behavior, :term:`DEBIAN_NOAUTONAME` specifies a 1781 particular package should not be renamed according to Debian library 1782 package naming. You must use the package name as an override when you 1783 set this variable. Here is an example from the ``fontconfig`` recipe:: 1784 1785 DEBIAN_NOAUTONAME:fontconfig-utils = "1" 1786 1787 :term:`DEBIANNAME` 1788 When the :ref:`ref-classes-debian` class is inherited, 1789 which is the default behavior, :term:`DEBIANNAME` allows you to override 1790 the library name for an individual package. Overriding the library 1791 name in these cases is rare. You must use the package name as an 1792 override when you set this variable. Here is an example from the 1793 ``dbus`` recipe:: 1794 1795 DEBIANNAME:${PN} = "dbus-1" 1796 1797 :term:`DEBUG_BUILD` 1798 Specifies to build packages with debugging information. This 1799 influences the value of the :term:`SELECTED_OPTIMIZATION` variable. 1800 1801 :term:`DEBUG_OPTIMIZATION` 1802 The options to pass in :term:`TARGET_CFLAGS` and :term:`CFLAGS` when 1803 compiling a system for debugging. This variable defaults to "-O 1804 -fno-omit-frame-pointer ${DEBUG_FLAGS} -pipe". 1805 1806 :term:`DEBUG_PREFIX_MAP` 1807 Allows to set C compiler options, such as ``-fdebug-prefix-map``, 1808 ``-fmacro-prefix-map``, and ``-ffile-prefix-map``, which allow to 1809 replace build-time paths by install-time ones in the debugging sections 1810 of binaries. This makes compiler output files location independent, 1811 at the cost of having to pass an extra command to tell the debugger 1812 where source files are. 1813 1814 This is used by the Yocto Project to guarantee 1815 :doc:`/test-manual/reproducible-builds` even when the source code of 1816 a package uses the ``__FILE__`` or ``assert()`` macros. See the 1817 `reproducible-builds.org <https://reproducible-builds.org/docs/build-path/>`__ 1818 website for details. 1819 1820 This variable is set in the ``meta/conf/bitbake.conf`` file. It is 1821 not intended to be user-configurable. 1822 1823 :term:`DEFAULT_PREFERENCE` 1824 Specifies a weak bias for recipe selection priority. 1825 1826 The most common usage of this is variable is to set it to "-1" within 1827 a recipe for a development version of a piece of software. Using the 1828 variable in this way causes the stable version of the recipe to build 1829 by default in the absence of :term:`PREFERRED_VERSION` being used to 1830 build the development version. 1831 1832 .. note:: 1833 1834 The bias provided by :term:`DEFAULT_PREFERENCE` is weak and is overridden 1835 by :term:`BBFILE_PRIORITY` if that variable is different between two 1836 layers that contain different versions of the same recipe. 1837 1838 :term:`DEFAULTTUNE` 1839 The default CPU and Application Binary Interface (ABI) tunings (i.e. 1840 the "tune") used by the OpenEmbedded build system. The 1841 :term:`DEFAULTTUNE` helps define 1842 :term:`TUNE_FEATURES`. 1843 1844 The default tune is either implicitly or explicitly set by the 1845 machine (:term:`MACHINE`). However, you can override 1846 the setting using available tunes as defined with 1847 :term:`AVAILTUNES`. 1848 1849 :term:`DEPENDS` 1850 Lists a recipe's build-time dependencies. These are dependencies on 1851 other recipes whose contents (e.g. headers and shared libraries) are 1852 needed by the recipe at build time. 1853 1854 As an example, consider a recipe ``foo`` that contains the following 1855 assignment:: 1856 1857 DEPENDS = "bar" 1858 1859 The practical effect of the previous assignment is that all files 1860 installed by bar will be available in the appropriate staging sysroot, 1861 given by the :term:`STAGING_DIR* <STAGING_DIR>` variables, by the time 1862 the :ref:`ref-tasks-configure` task for ``foo`` runs. This mechanism is 1863 implemented by having :ref:`ref-tasks-configure` depend on the 1864 :ref:`ref-tasks-populate_sysroot` task of each recipe listed in 1865 :term:`DEPENDS`, through a 1866 ``[``\ :ref:`deptask <bitbake-user-manual/bitbake-user-manual-metadata:variable flags>`\ ``]`` 1867 declaration in the :ref:`ref-classes-base` class. 1868 1869 .. note:: 1870 1871 It seldom is necessary to reference, for example, :term:`STAGING_DIR_HOST` 1872 explicitly. The standard classes and build-related variables are 1873 configured to automatically use the appropriate staging sysroots. 1874 1875 As another example, :term:`DEPENDS` can also be used to add utilities 1876 that run on the build machine during the build. For example, a recipe 1877 that makes use of a code generator built by the recipe ``codegen`` 1878 might have the following:: 1879 1880 DEPENDS = "codegen-native" 1881 1882 For more 1883 information, see the :ref:`ref-classes-native` class and 1884 the :term:`EXTRANATIVEPATH` variable. 1885 1886 .. note:: 1887 1888 - :term:`DEPENDS` is a list of recipe names. Or, to be more precise, 1889 it is a list of :term:`PROVIDES` names, which 1890 usually match recipe names. Putting a package name such as 1891 "foo-dev" in :term:`DEPENDS` does not make sense. Use "foo" 1892 instead, as this will put files from all the packages that make 1893 up ``foo``, which includes those from ``foo-dev``, into the 1894 sysroot. 1895 1896 - One recipe having another recipe in :term:`DEPENDS` does not by 1897 itself add any runtime dependencies between the packages 1898 produced by the two recipes. However, as explained in the 1899 ":ref:`overview-manual/concepts:automatically added runtime dependencies`" 1900 section in the Yocto Project Overview and Concepts Manual, 1901 runtime dependencies will often be added automatically, meaning 1902 :term:`DEPENDS` alone is sufficient for most recipes. 1903 1904 - Counterintuitively, :term:`DEPENDS` is often necessary even for 1905 recipes that install precompiled components. For example, if 1906 ``libfoo`` is a precompiled library that links against 1907 ``libbar``, then linking against ``libfoo`` requires both 1908 ``libfoo`` and ``libbar`` to be available in the sysroot. 1909 Without a :term:`DEPENDS` from the recipe that installs ``libfoo`` 1910 to the recipe that installs ``libbar``, other recipes might 1911 fail to link against ``libfoo``. 1912 1913 For information on runtime dependencies, see the :term:`RDEPENDS` 1914 variable. You can also see the 1915 ":ref:`bitbake-user-manual/bitbake-user-manual-metadata:tasks`" and 1916 ":ref:`bitbake-user-manual/bitbake-user-manual-execution:dependencies`" 1917 sections in the BitBake User Manual for additional information on tasks 1918 and dependencies. 1919 1920 :term:`DEPLOY_DIR` 1921 Points to the general area that the OpenEmbedded build system uses to 1922 place images, packages, SDKs, and other output files that are ready 1923 to be used outside of the build system. By default, this directory 1924 resides within the :term:`Build Directory` as ``${TMPDIR}/deploy``. 1925 1926 For more information on the structure of the Build Directory, see 1927 ":ref:`ref-manual/structure:the build directory --- \`\`build/\`\``" section. 1928 For more detail on the contents of the ``deploy`` directory, see the 1929 ":ref:`overview-manual/concepts:images`", 1930 ":ref:`overview-manual/concepts:package feeds`", and 1931 ":ref:`overview-manual/concepts:application development sdk`" sections all in the 1932 Yocto Project Overview and Concepts Manual. 1933 1934 :term:`DEPLOY_DIR_DEB` 1935 Points to the area that the OpenEmbedded build system uses to place 1936 Debian packages that are ready to be used outside of the build 1937 system. This variable applies only when :term:`PACKAGE_CLASSES` contains 1938 ":ref:`ref-classes-package_deb`". 1939 1940 The BitBake configuration file initially defines the 1941 :term:`DEPLOY_DIR_DEB` variable as a sub-folder of 1942 :term:`DEPLOY_DIR`:: 1943 1944 DEPLOY_DIR_DEB = "${DEPLOY_DIR}/deb" 1945 1946 The :ref:`ref-classes-package_deb` class uses the 1947 :term:`DEPLOY_DIR_DEB` variable to make sure the 1948 :ref:`ref-tasks-package_write_deb` task 1949 writes Debian packages into the appropriate folder. For more 1950 information on how packaging works, see the 1951 ":ref:`overview-manual/concepts:package feeds`" section 1952 in the Yocto Project Overview and Concepts Manual. 1953 1954 :term:`DEPLOY_DIR_IMAGE` 1955 Points to the area that the OpenEmbedded build system uses to place 1956 images and other associated output files that are ready to be 1957 deployed onto the target machine. The directory is machine-specific 1958 as it contains the ``${MACHINE}`` name. By default, this directory 1959 resides within the :term:`Build Directory` as 1960 ``${DEPLOY_DIR}/images/${MACHINE}/``. 1961 1962 It must not be used directly in recipes when deploying files. Instead, 1963 it's only useful when a recipe needs to "read" a file already deployed 1964 by a dependency. So, it should be filled with the contents of 1965 :term:`DEPLOYDIR` by the :ref:`ref-classes-deploy` class or with the 1966 contents of :term:`IMGDEPLOYDIR` by the :ref:`ref-classes-image` class. 1967 1968 For more information on the structure of the :term:`Build Directory`, see 1969 ":ref:`ref-manual/structure:the build directory --- \`\`build/\`\``" section. 1970 For more detail on the contents of the ``deploy`` directory, see the 1971 ":ref:`overview-manual/concepts:images`" and 1972 ":ref:`overview-manual/concepts:application development sdk`" sections both in 1973 the Yocto Project Overview and Concepts Manual. 1974 1975 :term:`DEPLOY_DIR_IPK` 1976 Points to the area that the OpenEmbedded build system uses to place 1977 IPK packages that are ready to be used outside of the build system. 1978 This variable applies only when :term:`PACKAGE_CLASSES` contains 1979 ":ref:`ref-classes-package_ipk`". 1980 1981 The BitBake configuration file initially defines this variable as a 1982 sub-folder of :term:`DEPLOY_DIR`:: 1983 1984 DEPLOY_DIR_IPK = "${DEPLOY_DIR}/ipk" 1985 1986 The :ref:`ref-classes-package_ipk` class uses the :term:`DEPLOY_DIR_IPK` 1987 variable to make sure the :ref:`ref-tasks-package_write_ipk` task 1988 writes IPK packages into the appropriate folder. For more information 1989 on how packaging works, see the 1990 ":ref:`overview-manual/concepts:package feeds`" section 1991 in the Yocto Project Overview and Concepts Manual. 1992 1993 :term:`DEPLOY_DIR_RPM` 1994 Points to the area that the OpenEmbedded build system uses to place 1995 RPM packages that are ready to be used outside of the build system. 1996 This variable applies only when :term:`PACKAGE_CLASSES` contains 1997 ":ref:`ref-classes-package_rpm`". 1998 1999 The BitBake configuration file initially defines this variable as a 2000 sub-folder of :term:`DEPLOY_DIR`:: 2001 2002 DEPLOY_DIR_RPM = "${DEPLOY_DIR}/rpm" 2003 2004 The :ref:`ref-classes-package_rpm` class uses the 2005 :term:`DEPLOY_DIR_RPM` variable to make sure the 2006 :ref:`ref-tasks-package_write_rpm` task 2007 writes RPM packages into the appropriate folder. For more information 2008 on how packaging works, see the 2009 ":ref:`overview-manual/concepts:package feeds`" section 2010 in the Yocto Project Overview and Concepts Manual. 2011 2012 :term:`DEPLOYDIR` 2013 When inheriting the :ref:`ref-classes-deploy` class, the 2014 :term:`DEPLOYDIR` points to a temporary work area for deployed files that 2015 is set in the :ref:`ref-classes-deploy` class as follows:: 2016 2017 DEPLOYDIR = "${WORKDIR}/deploy-${PN}" 2018 2019 Recipes inheriting the :ref:`ref-classes-deploy` class should copy files to be 2020 deployed into :term:`DEPLOYDIR`, and the class will take care of copying 2021 them into :term:`DEPLOY_DIR_IMAGE` 2022 afterwards. 2023 2024 :term:`DESCRIPTION` 2025 The package description used by package managers. If not set, 2026 :term:`DESCRIPTION` takes the value of the :term:`SUMMARY` 2027 variable. 2028 2029 :term:`DEV_PKG_DEPENDENCY` 2030 Provides an easy way for recipes to disable or adjust the runtime recommendation 2031 (:term:`RRECOMMENDS`) of the ``${PN}-dev`` package on the main 2032 (``${PN}``) package. 2033 2034 :term:`DISABLE_STATIC` 2035 Used in order to disable static linking by default (in order to save 2036 space, since static libraries are often unused in embedded systems.) 2037 The default value is " --disable-static", however it can be set to "" 2038 in order to enable static linking if desired. Certain recipes do this 2039 individually, and also there is a 2040 ``meta/conf/distro/include/no-static-libs.inc`` include file that 2041 disables static linking for a number of recipes. Some software 2042 packages or build tools (such as CMake) have explicit support for 2043 enabling / disabling static linking, and in those cases 2044 :term:`DISABLE_STATIC` is not used. 2045 2046 :term:`DISTRO` 2047 The short name of the distribution. For information on the long name 2048 of the distribution, see the :term:`DISTRO_NAME` 2049 variable. 2050 2051 The :term:`DISTRO` variable corresponds to a distribution configuration 2052 file whose root name is the same as the variable's argument and whose 2053 filename extension is ``.conf``. For example, the distribution 2054 configuration file for the Poky distribution is named ``poky.conf`` 2055 and resides in the ``meta-poky/conf/distro`` directory of the 2056 :term:`Source Directory`. 2057 2058 Within that ``poky.conf`` file, the :term:`DISTRO` variable is set as 2059 follows:: 2060 2061 DISTRO = "poky" 2062 2063 Distribution configuration files are located in a ``conf/distro`` 2064 directory within the :term:`Metadata` that contains the 2065 distribution configuration. The value for :term:`DISTRO` must not contain 2066 spaces, and is typically all lower-case. 2067 2068 .. note:: 2069 2070 If the :term:`DISTRO` variable is blank, a set of default configurations 2071 are used, which are specified within 2072 ``meta/conf/distro/defaultsetup.conf`` also in the Source Directory. 2073 2074 :term:`DISTRO_CODENAME` 2075 Specifies a codename for the distribution being built. 2076 2077 :term:`DISTRO_EXTRA_RDEPENDS` 2078 Specifies a list of distro-specific packages to add to all images. 2079 This variable takes effect through ``packagegroup-base`` so the 2080 variable only really applies to the more full-featured images that 2081 include ``packagegroup-base``. You can use this variable to keep 2082 distro policy out of generic images. As with all other distro 2083 variables, you set this variable in the distro ``.conf`` file. 2084 2085 :term:`DISTRO_EXTRA_RRECOMMENDS` 2086 Specifies a list of distro-specific packages to add to all images if 2087 the packages exist. The packages might not exist or be empty (e.g. 2088 kernel modules). The list of packages are automatically installed but 2089 you can remove them. 2090 2091 :term:`DISTRO_FEATURES` 2092 The software support you want in your distribution for various 2093 features. You define your distribution features in the distribution 2094 configuration file. 2095 2096 In most cases, the presence or absence of a feature in 2097 :term:`DISTRO_FEATURES` is translated to the appropriate option supplied 2098 to the configure script during the 2099 :ref:`ref-tasks-configure` task for recipes that 2100 optionally support the feature. For example, specifying "x11" in 2101 :term:`DISTRO_FEATURES`, causes every piece of software built for the 2102 target that can optionally support X11 to have its X11 support 2103 enabled. 2104 2105 .. note:: 2106 2107 Just enabling :term:`DISTRO_FEATURES` alone doesn't 2108 enable feature support for packages. Mechanisms such as making 2109 :term:`PACKAGECONFIG` track :term:`DISTRO_FEATURES` are used 2110 to enable/disable package features. 2111 2112 Two more examples are Bluetooth and NFS support. For a more complete 2113 list of features that ships with the Yocto Project and that you can 2114 provide with this variable, see the ":ref:`ref-features-distro`" section. 2115 2116 :term:`DISTRO_FEATURES_BACKFILL` 2117 A space-separated list of features to be added to :term:`DISTRO_FEATURES` 2118 if not also present in :term:`DISTRO_FEATURES_BACKFILL_CONSIDERED`. 2119 2120 This variable is set in the ``meta/conf/bitbake.conf`` file. It is 2121 not intended to be user-configurable. It is best to just reference 2122 the variable to see which distro features are being 2123 :ref:`backfilled <ref-features-backfill>` for all distro configurations. 2124 2125 :term:`DISTRO_FEATURES_BACKFILL_CONSIDERED` 2126 A space-separated list of features from :term:`DISTRO_FEATURES_BACKFILL` 2127 that should not be :ref:`backfilled <ref-features-backfill>` (i.e. added 2128 to :term:`DISTRO_FEATURES`) during the build. 2129 2130 This corresponds to an opt-out mechanism. When new default distro 2131 features are introduced, distribution maintainers can review (`consider`) 2132 them and decide to exclude them from the 2133 :ref:`backfilled <ref-features-backfill>` features. Therefore, the 2134 combination of :term:`DISTRO_FEATURES_BACKFILL` and 2135 :term:`DISTRO_FEATURES_BACKFILL_CONSIDERED` makes it possible to 2136 add new default features without breaking existing distributions. 2137 2138 2139 :term:`DISTRO_FEATURES_DEFAULT` 2140 A convenience variable that gives you the default list of distro 2141 features with the exception of any features specific to the C library 2142 (``libc``). 2143 2144 When creating a custom distribution, you might find it useful to be 2145 able to reuse the default 2146 :term:`DISTRO_FEATURES` options without the 2147 need to write out the full set. Here is an example that uses 2148 :term:`DISTRO_FEATURES_DEFAULT` from a custom distro configuration file:: 2149 2150 DISTRO_FEATURES ?= "${DISTRO_FEATURES_DEFAULT} myfeature" 2151 2152 :term:`DISTRO_FEATURES_FILTER_NATIVE` 2153 Specifies a list of features that if present in the target 2154 :term:`DISTRO_FEATURES` value should be 2155 included in :term:`DISTRO_FEATURES` when building native recipes. This 2156 variable is used in addition to the features filtered using the 2157 :term:`DISTRO_FEATURES_NATIVE` 2158 variable. 2159 2160 :term:`DISTRO_FEATURES_FILTER_NATIVESDK` 2161 Specifies a list of features that if present in the target 2162 :term:`DISTRO_FEATURES` value should be included in 2163 :term:`DISTRO_FEATURES` when building :ref:`ref-classes-nativesdk` 2164 recipes. This variable is used in addition to the features filtered using 2165 the :term:`DISTRO_FEATURES_NATIVESDK` variable. 2166 2167 :term:`DISTRO_FEATURES_NATIVE` 2168 Specifies a list of features that should be included in 2169 :term:`DISTRO_FEATURES` when building native 2170 recipes. This variable is used in addition to the features filtered 2171 using the 2172 :term:`DISTRO_FEATURES_FILTER_NATIVE` 2173 variable. 2174 2175 :term:`DISTRO_FEATURES_NATIVESDK` 2176 Specifies a list of features that should be included in 2177 :term:`DISTRO_FEATURES` when building 2178 :ref:`ref-classes-nativesdk` recipes. This variable is used 2179 in addition to the features filtered using the 2180 :term:`DISTRO_FEATURES_FILTER_NATIVESDK` variable. 2181 2182 :term:`DISTRO_NAME` 2183 The long name of the distribution. For information on the short name 2184 of the distribution, see the :term:`DISTRO` variable. 2185 2186 The :term:`DISTRO_NAME` variable corresponds to a distribution 2187 configuration file whose root name is the same as the variable's 2188 argument and whose filename extension is ``.conf``. For example, the 2189 distribution configuration file for the Poky distribution is named 2190 ``poky.conf`` and resides in the ``meta-poky/conf/distro`` directory 2191 of the :term:`Source Directory`. 2192 2193 Within that ``poky.conf`` file, the :term:`DISTRO_NAME` variable is set 2194 as follows:: 2195 2196 DISTRO_NAME = "Poky (Yocto Project Reference Distro)" 2197 2198 Distribution configuration files are located in a ``conf/distro`` 2199 directory within the :term:`Metadata` that contains the 2200 distribution configuration. 2201 2202 .. note:: 2203 2204 If the :term:`DISTRO_NAME` variable is blank, a set of default 2205 configurations are used, which are specified within 2206 ``meta/conf/distro/defaultsetup.conf`` also in the Source Directory. 2207 2208 :term:`DISTRO_VERSION` 2209 The version of the distribution. 2210 2211 :term:`DISTROOVERRIDES` 2212 A colon-separated list of overrides specific to the current 2213 distribution. By default, this list includes the value of 2214 :term:`DISTRO`. 2215 2216 You can extend :term:`DISTROOVERRIDES` to add extra overrides that should 2217 apply to the distribution. 2218 2219 The underlying mechanism behind :term:`DISTROOVERRIDES` is simply that it 2220 is included in the default value of 2221 :term:`OVERRIDES`. 2222 2223 Here is an example from :yocto_git:`meta-poky/conf/distro/poky-tiny.conf 2224 </poky/tree/meta-poky/conf/distro/poky-tiny.conf>`:: 2225 2226 DISTROOVERRIDES = "poky:poky-tiny" 2227 2228 :term:`DL_DIR` 2229 The central download directory used by the build process to store 2230 downloads. By default, :term:`DL_DIR` gets files suitable for mirroring 2231 for everything except Git repositories. If you want tarballs of Git 2232 repositories, use the 2233 :term:`BB_GENERATE_MIRROR_TARBALLS` 2234 variable. 2235 2236 You can set this directory by defining the :term:`DL_DIR` variable in the 2237 ``conf/local.conf`` file. This directory is self-maintaining and you 2238 should not have to touch it. By default, the directory is 2239 ``downloads`` in the :term:`Build Directory`:: 2240 2241 #DL_DIR ?= "${TOPDIR}/downloads" 2242 2243 To specify a different download directory, 2244 simply remove the comment from the line and provide your directory. 2245 2246 During a first build, the system downloads many different source code 2247 tarballs from various upstream projects. Downloading can take a 2248 while, particularly if your network connection is slow. Tarballs are 2249 all stored in the directory defined by :term:`DL_DIR` and the build 2250 system looks there first to find source tarballs. 2251 2252 .. note:: 2253 2254 When wiping and rebuilding, you can preserve this directory to 2255 speed up this part of subsequent builds. 2256 2257 You can safely share this directory between multiple builds on the 2258 same development machine. For additional information on how the build 2259 process gets source files when working behind a firewall or proxy 2260 server, see this specific question in the ":doc:`faq`" 2261 chapter. You can also refer to the 2262 ":yocto_wiki:`Working Behind a Network Proxy </Working_Behind_a_Network_Proxy>`" 2263 Wiki page. 2264 2265 :term:`DOC_COMPRESS` 2266 When inheriting the :ref:`ref-classes-compress_doc` 2267 class, this variable sets the compression policy used when the 2268 OpenEmbedded build system compresses man pages and info pages. By 2269 default, the compression method used is gz (gzip). Other policies 2270 available are xz and bz2. 2271 2272 For information on policies and on how to use this variable, see the 2273 comments in the ``meta/classes-recipe/compress_doc.bbclass`` file. 2274 2275 :term:`DT_FILES` 2276 Space-separated list of device tree source files to compile using 2277 a recipe that inherits the :ref:`ref-classes-devicetree` class. These 2278 are relative to the :term:`DT_FILES_PATH`. 2279 2280 For convenience, both ``.dts`` and ``.dtb`` extensions can be used. 2281 2282 Use an empty string (default) to build all device tree sources within 2283 the :term:`DT_FILES_PATH` directory. 2284 2285 :term:`DT_FILES_PATH` 2286 When compiling out-of-tree device tree sources using a recipe that 2287 inherits the :ref:`ref-classes-devicetree` class, this variable specifies 2288 the path to the directory containing dts files to build. 2289 2290 Defaults to the :term:`S` directory. 2291 2292 :term:`DT_PADDING_SIZE` 2293 When inheriting the :ref:`ref-classes-devicetree` class, this variable 2294 specifies the size of padding appended to the device tree blob, used as 2295 extra space typically for additional properties during boot. 2296 2297 :term:`EFI_PROVIDER` 2298 When building bootable images (i.e. where ``hddimg``, ``iso``, or 2299 ``wic.vmdk`` is in :term:`IMAGE_FSTYPES`), the 2300 :term:`EFI_PROVIDER` variable specifies the EFI bootloader to use. The 2301 default is "grub-efi", but "systemd-boot" can be used instead. 2302 2303 See the :ref:`ref-classes-systemd-boot` and :ref:`ref-classes-image-live` 2304 classes for more information. 2305 2306 :term:`ENABLE_BINARY_LOCALE_GENERATION` 2307 Variable that controls which locales for ``glibc`` are generated 2308 during the build (useful if the target device has 64Mbytes of RAM or 2309 less). 2310 2311 :term:`ERR_REPORT_DIR` 2312 When used with the :ref:`ref-classes-report-error` class, specifies the 2313 path used for storing the debug files created by the :ref:`error reporting 2314 tool <dev-manual/error-reporting-tool:using the error reporting tool>`, 2315 which allows you to submit build errors you encounter to a central 2316 database. By default, the value of this variable is 2317 ``${``\ :term:`LOG_DIR`\ ``}/error-report``. 2318 2319 You can set :term:`ERR_REPORT_DIR` to the path you want the error 2320 reporting tool to store the debug files as follows in your 2321 ``local.conf`` file:: 2322 2323 ERR_REPORT_DIR = "path" 2324 2325 :term:`ERROR_QA` 2326 Specifies the quality assurance checks whose failures are reported as 2327 errors by the OpenEmbedded build system. You set this variable in 2328 your distribution configuration file. For a list of the checks you 2329 can control with this variable, see the 2330 ":ref:`ref-classes-insane`" section. 2331 2332 :term:`ESDK_CLASS_INHERIT_DISABLE` 2333 A list of classes to remove from the :term:`INHERIT` 2334 value globally within the extensible SDK configuration. The 2335 :ref:`populate-sdk-ext <ref-classes-populate-sdk-*>` class sets the 2336 default value:: 2337 2338 ESDK_CLASS_INHERIT_DISABLE ?= "buildhistory icecc" 2339 2340 Some classes are not generally applicable within the extensible SDK 2341 context. You can use this variable to disable those classes. 2342 2343 For additional information on how to customize the extensible SDK's 2344 configuration, see the 2345 ":ref:`sdk-manual/appendix-customizing:configuring the extensible sdk`" 2346 section in the Yocto Project Application Development and the 2347 Extensible Software Development Kit (eSDK) manual. 2348 2349 :term:`ESDK_LOCALCONF_ALLOW` 2350 A list of variables allowed through from the OpenEmbedded build 2351 system configuration into the extensible SDK configuration. By 2352 default, the list of variables is empty and is set in the 2353 :ref:`populate-sdk-ext <ref-classes-populate-sdk-*>` class. 2354 2355 This list overrides the variables specified using the 2356 :term:`ESDK_LOCALCONF_REMOVE` variable as well as 2357 other variables automatically added due to the "/" character 2358 being found at the start of the 2359 value, which is usually indicative of being a path and thus might not 2360 be valid on the system where the SDK is installed. 2361 2362 For additional information on how to customize the extensible SDK's 2363 configuration, see the 2364 ":ref:`sdk-manual/appendix-customizing:configuring the extensible sdk`" 2365 section in the Yocto Project Application Development and the 2366 Extensible Software Development Kit (eSDK) manual. 2367 2368 :term:`ESDK_LOCALCONF_REMOVE` 2369 A list of variables not allowed through from the OpenEmbedded build 2370 system configuration into the extensible SDK configuration. Usually, 2371 these are variables that are specific to the machine on which the 2372 build system is running and thus would be potentially problematic 2373 within the extensible SDK. 2374 2375 By default, :term:`ESDK_LOCALCONF_REMOVE` is set in the 2376 :ref:`populate-sdk-ext <ref-classes-populate-sdk-*>` class and 2377 excludes the following variables: 2378 2379 - :term:`CONF_VERSION` 2380 - :term:`BB_NUMBER_THREADS` 2381 - :term:`BB_NUMBER_PARSE_THREADS` 2382 - :term:`PARALLEL_MAKE` 2383 - :term:`PRSERV_HOST` 2384 - :term:`SSTATE_MIRRORS` :term:`DL_DIR` 2385 - :term:`SSTATE_DIR` :term:`TMPDIR` 2386 - :term:`BB_SERVER_TIMEOUT` 2387 2388 For additional information on how to customize the extensible SDK's 2389 configuration, see the 2390 ":ref:`sdk-manual/appendix-customizing:configuring the extensible sdk`" 2391 section in the Yocto Project Application Development and the 2392 Extensible Software Development Kit (eSDK) manual. 2393 2394 :term:`EXCLUDE_FROM_SHLIBS` 2395 Triggers the OpenEmbedded build system's shared libraries resolver to 2396 exclude an entire package when scanning for shared libraries. 2397 2398 .. note:: 2399 2400 The shared libraries resolver's functionality results in part from 2401 the internal function ``package_do_shlibs``, which is part of the 2402 :ref:`ref-tasks-package` task. You should be aware that the shared 2403 libraries resolver might implicitly define some dependencies between 2404 packages. 2405 2406 The :term:`EXCLUDE_FROM_SHLIBS` variable is similar to the 2407 :term:`PRIVATE_LIBS` variable, which excludes a 2408 package's particular libraries only and not the whole package. 2409 2410 Use the :term:`EXCLUDE_FROM_SHLIBS` variable by setting it to "1" for a 2411 particular package:: 2412 2413 EXCLUDE_FROM_SHLIBS = "1" 2414 2415 :term:`EXCLUDE_FROM_WORLD` 2416 Directs BitBake to exclude a recipe from world builds (i.e. 2417 ``bitbake world``). During world builds, BitBake locates, parses and 2418 builds all recipes found in every layer exposed in the 2419 ``bblayers.conf`` configuration file. 2420 2421 To exclude a recipe from a world build using this variable, set the 2422 variable to "1" in the recipe. 2423 2424 .. note:: 2425 2426 Recipes added to :term:`EXCLUDE_FROM_WORLD` may still be built during a 2427 world build in order to satisfy dependencies of other recipes. Adding 2428 a recipe to :term:`EXCLUDE_FROM_WORLD` only ensures that the recipe is not 2429 explicitly added to the list of build targets in a world build. 2430 2431 :term:`EXTENDPE` 2432 Used with file and pathnames to create a prefix for a recipe's 2433 version based on the recipe's :term:`PE` value. If :term:`PE` 2434 is set and greater than zero for a recipe, :term:`EXTENDPE` becomes that 2435 value (e.g if :term:`PE` is equal to "1" then :term:`EXTENDPE` becomes "1"). 2436 If a recipe's :term:`PE` is not set (the default) or is equal to zero, 2437 :term:`EXTENDPE` becomes "". 2438 2439 See the :term:`STAMP` variable for an example. 2440 2441 :term:`EXTENDPKGV` 2442 The full package version specification as it appears on the final 2443 packages produced by a recipe. The variable's value is normally used 2444 to fix a runtime dependency to the exact same version of another 2445 package in the same recipe:: 2446 2447 RDEPENDS:${PN}-additional-module = "${PN} (= ${EXTENDPKGV})" 2448 2449 The dependency relationships are intended to force the package 2450 manager to upgrade these types of packages in lock-step. 2451 2452 :term:`EXTERNAL_KERNEL_TOOLS` 2453 When set, the :term:`EXTERNAL_KERNEL_TOOLS` variable indicates that these 2454 tools are not in the source tree. 2455 2456 When kernel tools are available in the tree, they are preferred over 2457 any externally installed tools. Setting the :term:`EXTERNAL_KERNEL_TOOLS` 2458 variable tells the OpenEmbedded build system to prefer the installed 2459 external tools. See the :ref:`ref-classes-kernel-yocto` class in 2460 ``meta/classes-recipe`` to see how the variable is used. 2461 2462 :term:`EXTERNAL_TOOLCHAIN` 2463 When you intend to use an 2464 :ref:`external toolchain <dev-manual/external-toolchain:optionally using an external toolchain>`, 2465 this variable allows to specify the directory where this toolchain was 2466 installed. 2467 2468 :term:`EXTERNALSRC` 2469 When inheriting the :ref:`ref-classes-externalsrc` 2470 class, this variable points to the source tree, which is outside of 2471 the OpenEmbedded build system. When set, this variable sets the 2472 :term:`S` variable, which is what the OpenEmbedded build 2473 system uses to locate unpacked recipe source code. 2474 2475 See the ":ref:`ref-classes-externalsrc`" section for details. You 2476 can also find information on how to use this variable in the 2477 ":ref:`dev-manual/building:building software from an external source`" 2478 section in the Yocto Project Development Tasks Manual. 2479 2480 :term:`EXTERNALSRC_BUILD` 2481 When inheriting the :ref:`ref-classes-externalsrc` 2482 class, this variable points to the directory in which the recipe's 2483 source code is built, which is outside of the OpenEmbedded build 2484 system. When set, this variable sets the :term:`B` variable, 2485 which is what the OpenEmbedded build system uses to locate the 2486 :term:`Build Directory`. 2487 2488 See the ":ref:`ref-classes-externalsrc`" section for details. You 2489 can also find information on how to use this variable in the 2490 ":ref:`dev-manual/building:building software from an external source`" 2491 section in the Yocto Project Development Tasks Manual. 2492 2493 :term:`EXTRA_AUTORECONF` 2494 For recipes inheriting the :ref:`ref-classes-autotools` 2495 class, you can use :term:`EXTRA_AUTORECONF` to specify extra options to 2496 pass to the ``autoreconf`` command that is executed during the 2497 :ref:`ref-tasks-configure` task. 2498 2499 The default value is "--exclude=autopoint". 2500 2501 :term:`EXTRA_IMAGE_FEATURES` 2502 A list of additional features to include in an image. When listing 2503 more than one feature, separate them with a space. 2504 2505 Typically, you configure this variable in your ``local.conf`` file, 2506 which is found in the :term:`Build Directory`. Although you can use this 2507 variable from within a recipe, best practices dictate that you do not. 2508 2509 .. note:: 2510 2511 To enable primary features from within the image recipe, use the 2512 :term:`IMAGE_FEATURES` variable. 2513 2514 Here are some examples of features you can add: 2515 2516 - "dbg-pkgs" --- adds -dbg packages for all installed packages including 2517 symbol information for debugging and profiling. 2518 2519 - "debug-tweaks" --- makes an image suitable for debugging. For example, allows root logins without passwords and 2520 enables post-installation logging. See the 'allow-empty-password' and 2521 'post-install-logging' features in the ":ref:`ref-features-image`" 2522 section for more information. 2523 - "dev-pkgs" --- adds -dev packages for all installed packages. This is 2524 useful if you want to develop against the libraries in the image. 2525 - "read-only-rootfs" --- creates an image whose root filesystem is 2526 read-only. See the 2527 ":ref:`dev-manual/read-only-rootfs:creating a read-only root filesystem`" 2528 section in the Yocto Project Development Tasks Manual for more 2529 information 2530 - "tools-debug" --- adds debugging tools such as gdb and strace. 2531 - "tools-sdk" --- adds development tools such as gcc, make, 2532 pkgconfig and so forth. 2533 - "tools-testapps" --- adds useful testing tools 2534 such as ts_print, aplay, arecord and so forth. 2535 2536 For a complete list of image features that ships with the Yocto 2537 Project, see the ":ref:`ref-features-image`" section. 2538 2539 For an example that shows how to customize your image by using this 2540 variable, see the ":ref:`dev-manual/customizing-images:customizing images using custom \`\`image_features\`\` and \`\`extra_image_features\`\``" 2541 section in the Yocto Project Development Tasks Manual. 2542 2543 :term:`EXTRA_IMAGECMD` 2544 Specifies additional options for the image creation command that has 2545 been specified in :term:`IMAGE_CMD`. When setting 2546 this variable, use an override for the associated image type. Here is 2547 an example:: 2548 2549 EXTRA_IMAGECMD:ext3 ?= "-i 4096" 2550 2551 :term:`EXTRA_IMAGEDEPENDS` 2552 A list of recipes to build that do not provide packages for 2553 installing into the root filesystem. 2554 2555 Sometimes a recipe is required to build the final image but is not 2556 needed in the root filesystem. You can use the :term:`EXTRA_IMAGEDEPENDS` 2557 variable to list these recipes and thus specify the dependencies. A 2558 typical example is a required bootloader in a machine configuration. 2559 2560 .. note:: 2561 2562 To add packages to the root filesystem, see the various 2563 :term:`RDEPENDS` and :term:`RRECOMMENDS` variables. 2564 2565 :term:`EXTRA_OECMAKE` 2566 Additional `CMake <https://cmake.org/overview/>`__ options. See the 2567 :ref:`ref-classes-cmake` class for additional information. 2568 2569 :term:`EXTRA_OECONF` 2570 Additional ``configure`` script options. See 2571 :term:`PACKAGECONFIG_CONFARGS` for 2572 additional information on passing configure script options. 2573 2574 :term:`EXTRA_OEMAKE` 2575 Additional GNU ``make`` options. 2576 2577 Because the :term:`EXTRA_OEMAKE` defaults to "", you need to set the 2578 variable to specify any required GNU options. 2579 2580 :term:`PARALLEL_MAKE` and 2581 :term:`PARALLEL_MAKEINST` also make use of 2582 :term:`EXTRA_OEMAKE` to pass the required flags. 2583 2584 :term:`EXTRA_OESCONS` 2585 When inheriting the :ref:`ref-classes-scons` class, this 2586 variable specifies additional configuration options you want to pass 2587 to the ``scons`` command line. 2588 2589 :term:`EXTRA_OEMESON` 2590 Additional `Meson <https://mesonbuild.com/>`__ options. See the 2591 :ref:`ref-classes-meson` class for additional information. 2592 2593 In addition to standard Meson options, such options correspond to 2594 `Meson build options <https://mesonbuild.com/Build-options.html>`__ 2595 defined in the ``meson_options.txt`` file in the sources to build. 2596 Here is an example:: 2597 2598 EXTRA_OEMESON = "-Dpython=disabled -Dvalgrind=disabled" 2599 2600 Note that any custom value for the Meson ``--buildtype`` option 2601 should be set through the :term:`MESON_BUILDTYPE` variable. 2602 2603 :term:`EXTRA_USERS_PARAMS` 2604 When inheriting the :ref:`ref-classes-extrausers` 2605 class, this variable provides image level user and group operations. 2606 This is a more global method of providing user and group 2607 configuration as compared to using the 2608 :ref:`ref-classes-useradd` class, which ties user and 2609 group configurations to a specific recipe. 2610 2611 The set list of commands you can configure using the 2612 :term:`EXTRA_USERS_PARAMS` is shown in the 2613 :ref:`ref-classes-extrausers` class. These commands map to the normal 2614 Unix commands of the same names:: 2615 2616 # EXTRA_USERS_PARAMS = "\ 2617 # useradd -p '' tester; \ 2618 # groupadd developers; \ 2619 # userdel nobody; \ 2620 # groupdel -g video; \ 2621 # groupmod -g 1020 developers; \ 2622 # usermod -s /bin/sh tester; \ 2623 # " 2624 2625 Hardcoded passwords are supported via the ``-p`` parameters for 2626 ``useradd`` or ``usermod``, but only hashed. 2627 2628 Here is an example that adds two users named "tester-jim" and "tester-sue" and assigns 2629 passwords. First on host, create the (escaped) password hash:: 2630 2631 printf "%q" $(mkpasswd -m sha256crypt tester01) 2632 2633 The resulting hash is set to a variable and used in ``useradd`` command parameters:: 2634 2635 inherit extrausers 2636 PASSWD = "\$X\$ABC123\$A-Long-Hash" 2637 EXTRA_USERS_PARAMS = "\ 2638 useradd -p '${PASSWD}' tester-jim; \ 2639 useradd -p '${PASSWD}' tester-sue; \ 2640 " 2641 2642 Finally, here is an example that sets the root password:: 2643 2644 inherit extrausers 2645 EXTRA_USERS_PARAMS = "\ 2646 usermod -p '${PASSWD}' root; \ 2647 " 2648 2649 .. note:: 2650 2651 From a security perspective, hardcoding a default password is not 2652 generally a good idea or even legal in some jurisdictions. It is 2653 recommended that you do not do this if you are building a production 2654 image. 2655 2656 Additionally there is a special ``passwd-expire`` command that will 2657 cause the password for a user to be expired and thus force changing it 2658 on first login, for example:: 2659 2660 EXTRA_USERS_PARAMS += " useradd myuser; passwd-expire myuser;" 2661 2662 .. note:: 2663 2664 At present, ``passwd-expire`` may only work for remote logins when 2665 using OpenSSH and not dropbear as an SSH server. 2666 2667 :term:`EXTRANATIVEPATH` 2668 A list of subdirectories of 2669 ``${``\ :term:`STAGING_BINDIR_NATIVE`\ ``}`` 2670 added to the beginning of the environment variable ``PATH``. As an 2671 example, the following prepends 2672 "${STAGING_BINDIR_NATIVE}/foo:${STAGING_BINDIR_NATIVE}/bar:" to 2673 ``PATH``:: 2674 2675 EXTRANATIVEPATH = "foo bar" 2676 2677 :term:`FAKEROOT` 2678 See :term:`bitbake:FAKEROOT` in the BitBake manual. 2679 2680 :term:`FAKEROOTBASEENV` 2681 See :term:`bitbake:FAKEROOTBASEENV` in the BitBake manual. 2682 2683 :term:`FAKEROOTCMD` 2684 See :term:`bitbake:FAKEROOTCMD` in the BitBake manual. 2685 2686 :term:`FAKEROOTDIRS` 2687 See :term:`bitbake:FAKEROOTDIRS` in the BitBake manual. 2688 2689 :term:`FAKEROOTENV` 2690 See :term:`bitbake:FAKEROOTENV` in the BitBake manual. 2691 2692 :term:`FAKEROOTNOENV` 2693 See :term:`bitbake:FAKEROOTNOENV` in the BitBake manual. 2694 2695 :term:`FEATURE_PACKAGES` 2696 Defines one or more packages to include in an image when a specific 2697 item is included in :term:`IMAGE_FEATURES`. 2698 When setting the value, :term:`FEATURE_PACKAGES` should have the name of 2699 the feature item as an override. Here is an example:: 2700 2701 FEATURE_PACKAGES_widget = "package1 package2" 2702 2703 In this example, if "widget" were added to :term:`IMAGE_FEATURES`, 2704 package1 and package2 would be included in the image. 2705 2706 .. note:: 2707 2708 Packages installed by features defined through :term:`FEATURE_PACKAGES` 2709 are often package groups. While similarly named, you should not 2710 confuse the :term:`FEATURE_PACKAGES` variable with package groups, which 2711 are discussed elsewhere in the documentation. 2712 2713 :term:`FEED_DEPLOYDIR_BASE_URI` 2714 Points to the base URL of the server and location within the 2715 document-root that provides the metadata and packages required by 2716 OPKG to support runtime package management of IPK packages. You set 2717 this variable in your ``local.conf`` file. 2718 2719 Consider the following example:: 2720 2721 FEED_DEPLOYDIR_BASE_URI = "http://192.168.7.1/BOARD-dir" 2722 2723 This example assumes you are serving 2724 your packages over HTTP and your databases are located in a directory 2725 named ``BOARD-dir``, which is underneath your HTTP server's 2726 document-root. In this case, the OpenEmbedded build system generates 2727 a set of configuration files for you in your target that work with 2728 the feed. 2729 2730 :term:`FETCHCMD` 2731 See :term:`bitbake:FETCHCMD` in the BitBake manual. 2732 2733 :term:`FILE` 2734 See :term:`bitbake:FILE` in the BitBake manual. 2735 2736 :term:`FILES` 2737 The list of files and directories that are placed in a package. The 2738 :term:`PACKAGES` variable lists the packages 2739 generated by a recipe. 2740 2741 To use the :term:`FILES` variable, provide a package name override that 2742 identifies the resulting package. Then, provide a space-separated 2743 list of files or paths that identify the files you want included as 2744 part of the resulting package. Here is an example:: 2745 2746 FILES:${PN} += "${bindir}/mydir1 ${bindir}/mydir2/myfile" 2747 2748 .. note:: 2749 2750 - When specifying files or paths, you can pattern match using 2751 Python's 2752 `glob <https://docs.python.org/3/library/glob.html>`__ 2753 syntax. For details on the syntax, see the documentation by 2754 following the previous link. 2755 2756 - When specifying paths as part of the :term:`FILES` variable, it is 2757 good practice to use appropriate path variables. For example, 2758 use ``${sysconfdir}`` rather than ``/etc``, or ``${bindir}`` 2759 rather than ``/usr/bin``. You can find a list of these 2760 variables at the top of the ``meta/conf/bitbake.conf`` file in 2761 the :term:`Source Directory`. You will also 2762 find the default values of the various ``FILES:*`` variables in 2763 this file. 2764 2765 If some of the files you provide with the :term:`FILES` variable are 2766 editable and you know they should not be overwritten during the 2767 package update process by the Package Management System (PMS), you 2768 can identify these files so that the PMS will not overwrite them. See 2769 the :term:`CONFFILES` variable for information on 2770 how to identify these files to the PMS. 2771 2772 :term:`FILES_SOLIBSDEV` 2773 Defines the file specification to match 2774 :term:`SOLIBSDEV`. In other words, 2775 :term:`FILES_SOLIBSDEV` defines the full path name of the development 2776 symbolic link (symlink) for shared libraries on the target platform. 2777 2778 The following statement from the ``bitbake.conf`` shows how it is 2779 set:: 2780 2781 FILES_SOLIBSDEV ?= "${base_libdir}/lib*${SOLIBSDEV} ${libdir}/lib*${SOLIBSDEV}" 2782 2783 :term:`FILESEXTRAPATHS` 2784 A colon-separated list to extend the search path the OpenEmbedded build 2785 system uses when looking for files and patches as it processes recipes 2786 and append files. The default directories BitBake uses when it processes 2787 recipes are initially defined by the :term:`FILESPATH` variable. You can 2788 extend :term:`FILESPATH` variable by using :term:`FILESEXTRAPATHS`. 2789 2790 Best practices dictate that you accomplish this by using 2791 :term:`FILESEXTRAPATHS` from within a ``.bbappend`` file and that you 2792 prepend paths as follows:: 2793 2794 FILESEXTRAPATHS:prepend := "${THISDIR}/${PN}:" 2795 2796 In the above example, the build system first 2797 looks for files in a directory that has the same name as the 2798 corresponding append file. 2799 2800 .. note:: 2801 2802 When extending :term:`FILESEXTRAPATHS`, be sure to use the immediate 2803 expansion (``:=``) operator. Immediate expansion makes sure that 2804 BitBake evaluates :term:`THISDIR` at the time the 2805 directive is encountered rather than at some later time when 2806 expansion might result in a directory that does not contain the 2807 files you need. 2808 2809 Also, include the trailing separating colon character if you are 2810 prepending. The trailing colon character is necessary because you 2811 are directing BitBake to extend the path by prepending directories 2812 to the search path. 2813 2814 Here is another common use:: 2815 2816 FILESEXTRAPATHS:prepend := "${THISDIR}/files:" 2817 2818 In this example, the build system extends the 2819 :term:`FILESPATH` variable to include a directory named ``files`` that is 2820 in the same directory as the corresponding append file. 2821 2822 This next example specifically adds three paths:: 2823 2824 FILESEXTRAPATHS:prepend := "path_1:path_2:path_3:" 2825 2826 A final example shows how you can extend the search path and include 2827 a :term:`MACHINE`-specific override, which is useful 2828 in a BSP layer:: 2829 2830 FILESEXTRAPATHS:prepend:intel-x86-common := "${THISDIR}/${PN}:" 2831 2832 The previous statement appears in the 2833 ``linux-yocto-dev.bbappend`` file, which is found in the 2834 :ref:`overview-manual/development-environment:yocto project source repositories` in 2835 ``meta-intel/common/recipes-kernel/linux``. Here, the machine 2836 override is a special :term:`PACKAGE_ARCH` 2837 definition for multiple ``meta-intel`` machines. 2838 2839 .. note:: 2840 2841 For a layer that supports a single BSP, the override could just be 2842 the value of :term:`MACHINE`. 2843 2844 By prepending paths in ``.bbappend`` files, you allow multiple append 2845 files that reside in different layers but are used for the same 2846 recipe to correctly extend the path. 2847 2848 :term:`FILESOVERRIDES` 2849 A colon-separated list to specify a subset of :term:`OVERRIDES` used by 2850 the OpenEmbedded build system for creating :term:`FILESPATH`. The 2851 :term:`FILESOVERRIDES` variable uses overrides to automatically extend 2852 the :term:`FILESPATH` variable. For an example of how that works, see the 2853 :term:`FILESPATH` variable description. Additionally, you find more 2854 information on how overrides are handled in the 2855 ":ref:`bitbake-user-manual/bitbake-user-manual-metadata:conditional syntax (overrides)`" 2856 section of the BitBake User Manual. 2857 2858 By default, the :term:`FILESOVERRIDES` variable is defined as:: 2859 2860 FILESOVERRIDES = "${TRANSLATED_TARGET_ARCH}:${MACHINEOVERRIDES}:${DISTROOVERRIDES}" 2861 2862 .. note:: 2863 2864 Do not hand-edit the :term:`FILESOVERRIDES` variable. The values match up 2865 with expected overrides and are used in an expected manner by the 2866 build system. 2867 2868 :term:`FILESPATH` 2869 A colon-separated list specifying the default set of directories the 2870 OpenEmbedded build system uses when searching for patches and files. 2871 2872 During the build process, BitBake searches each directory in 2873 :term:`FILESPATH` in the specified order when looking for files and 2874 patches specified by each ``file://`` URI in a recipe's 2875 :term:`SRC_URI` statements. 2876 2877 The default value for the :term:`FILESPATH` variable is defined in the 2878 :ref:`ref-classes-base` class found in ``meta/classes-global`` in the 2879 :term:`Source Directory`:: 2880 2881 FILESPATH = "${@base_set_filespath(["${FILE_DIRNAME}/${BP}", \ 2882 "${FILE_DIRNAME}/${BPN}", "${FILE_DIRNAME}/files"], d)}" 2883 2884 The 2885 :term:`FILESPATH` variable is automatically extended using the overrides 2886 from the :term:`FILESOVERRIDES` variable. 2887 2888 .. note:: 2889 2890 - Do not hand-edit the :term:`FILESPATH` variable. If you want the 2891 build system to look in directories other than the defaults, 2892 extend the :term:`FILESPATH` variable by using the 2893 :term:`FILESEXTRAPATHS` variable. 2894 2895 - Be aware that the default :term:`FILESPATH` directories do not map 2896 to directories in custom layers where append files 2897 (``.bbappend``) are used. If you want the build system to find 2898 patches or files that reside with your append files, you need 2899 to extend the :term:`FILESPATH` variable by using the 2900 :term:`FILESEXTRAPATHS` variable. 2901 2902 You can take advantage of this searching behavior in useful ways. For 2903 example, consider a case where there is the following directory structure 2904 for general and machine-specific configurations:: 2905 2906 files/defconfig 2907 files/MACHINEA/defconfig 2908 files/MACHINEB/defconfig 2909 2910 Also in the example, the :term:`SRC_URI` statement contains 2911 "file://defconfig". Given this scenario, you can set 2912 :term:`MACHINE` to "MACHINEA" and cause the build 2913 system to use files from ``files/MACHINEA``. Set :term:`MACHINE` to 2914 "MACHINEB" and the build system uses files from ``files/MACHINEB``. 2915 Finally, for any machine other than "MACHINEA" and "MACHINEB", the 2916 build system uses files from ``files/defconfig``. 2917 2918 You can find out more about the patching process in the 2919 ":ref:`overview-manual/concepts:patching`" section 2920 in the Yocto Project Overview and Concepts Manual and the 2921 ":ref:`dev-manual/new-recipe:patching code`" section in 2922 the Yocto Project Development Tasks Manual. See the 2923 :ref:`ref-tasks-patch` task as well. 2924 2925 :term:`FILESYSTEM_PERMS_TABLES` 2926 Allows you to define your own file permissions settings table as part 2927 of your configuration for the packaging process. For example, suppose 2928 you need a consistent set of custom permissions for a set of groups 2929 and users across an entire work project. It is best to do this in the 2930 packages themselves but this is not always possible. 2931 2932 By default, the OpenEmbedded build system uses the ``fs-perms.txt``, 2933 which is located in the ``meta/files`` folder in the :term:`Source Directory`. 2934 If you create your own file 2935 permissions setting table, you should place it in your layer or the 2936 distro's layer. 2937 2938 You define the :term:`FILESYSTEM_PERMS_TABLES` variable in the 2939 ``conf/local.conf`` file, which is found in the :term:`Build Directory`, 2940 to point to your custom ``fs-perms.txt``. You can specify more than a 2941 single file permissions setting table. The paths you specify to these 2942 files must be defined within the :term:`BBPATH` variable. 2943 2944 For guidance on how to create your own file permissions settings 2945 table file, examine the existing ``fs-perms.txt``. 2946 2947 :term:`FIT_ADDRESS_CELLS` 2948 Specifies the value of the ``#address-cells`` value for the 2949 description of the FIT image. 2950 2951 The default value is set to "1" by the :ref:`ref-classes-kernel-fitimage` 2952 class, which corresponds to 32 bit addresses. 2953 2954 For platforms that need to set 64 bit addresses, for example in 2955 :term:`UBOOT_LOADADDRESS` and :term:`UBOOT_ENTRYPOINT`, you need to 2956 set this value to "2", as two 32 bit values (cells) will be needed 2957 to represent such addresses. 2958 2959 Here is an example setting "0x400000000" as a load address:: 2960 2961 FIT_ADDRESS_CELLS = "2" 2962 UBOOT_LOADADDRESS= "0x04 0x00000000" 2963 2964 See `more details about #address-cells <https://elinux.org/Device_Tree_Usage#How_Addressing_Works>`__. 2965 2966 :term:`FIT_CONF_DEFAULT_DTB` 2967 Specifies the default device tree binary (dtb) file for a FIT image 2968 when multiple ones are provided. 2969 2970 This variable is used in the :ref:`ref-classes-kernel-fitimage` class. 2971 2972 :term:`FIT_DESC` 2973 Specifies the description string encoded into a FIT image. The 2974 default value is set by the :ref:`ref-classes-kernel-fitimage` class as 2975 follows:: 2976 2977 FIT_DESC ?= "U-Boot fitImage for ${DISTRO_NAME}/${PV}/${MACHINE}" 2978 2979 :term:`FIT_GENERATE_KEYS` 2980 Decides whether to generate the keys for signing the FIT image if 2981 they don't already exist. The keys are created in 2982 :term:`UBOOT_SIGN_KEYDIR`. The default value is set to "0" 2983 by the :ref:`ref-classes-kernel-fitimage` class. 2984 2985 :term:`FIT_HASH_ALG` 2986 Specifies the hash algorithm used in creating the FIT Image. 2987 This variable is set by default to "sha256" by the 2988 :ref:`ref-classes-kernel-fitimage` class. 2989 2990 :term:`FIT_KERNEL_COMP_ALG` 2991 The compression algorithm to use for the kernel image inside the FIT Image. 2992 At present, the only supported values are "gzip" (default), "lzo" or "none". 2993 If you set this variable to anything other than "none" you may also need 2994 to set :term:`FIT_KERNEL_COMP_ALG_EXTENSION`. 2995 2996 This variable is used in the :ref:`ref-classes-kernel-uboot` class. 2997 2998 :term:`FIT_KERNEL_COMP_ALG_EXTENSION` 2999 File extension corresponding to :term:`FIT_KERNEL_COMP_ALG`. The default 3000 value is set ".gz" by the :ref:`ref-classes-kernel-uboot` class. If you 3001 set :term:`FIT_KERNEL_COMP_ALG` to "lzo", you may want to set this 3002 variable to ".lzo". 3003 3004 :term:`FIT_KEY_GENRSA_ARGS` 3005 Arguments to ``openssl genrsa`` for generating a RSA private key for 3006 signing the FIT image. The default value is set to "-F4" by the 3007 :ref:`ref-classes-kernel-fitimage` class. 3008 3009 :term:`FIT_KEY_REQ_ARGS` 3010 Arguments to ``openssl req`` for generating a certificate for signing 3011 the FIT image. The default value is "-batch -new" by the 3012 :ref:`ref-classes-kernel-fitimage` class, "batch" for 3013 non interactive mode and "new" for generating new keys. 3014 3015 :term:`FIT_KEY_SIGN_PKCS` 3016 Format for the public key certificate used for signing the FIT image. 3017 The default value is set to "x509" by the 3018 :ref:`ref-classes-kernel-fitimage` class. 3019 3020 :term:`FIT_SIGN_ALG` 3021 Specifies the signature algorithm used in creating the FIT Image. 3022 This variable is set by default to "rsa2048" by the 3023 :ref:`ref-classes-kernel-fitimage` class. 3024 3025 :term:`FIT_PAD_ALG` 3026 Specifies the padding algorithm used in creating the FIT Image. 3027 The default value is set to "pkcs-1.5" by the 3028 :ref:`ref-classes-kernel-fitimage` class. 3029 3030 :term:`FIT_SIGN_INDIVIDUAL` 3031 If set to "1", then the :ref:`ref-classes-kernel-fitimage` 3032 class will sign the kernel, dtb and ramdisk images individually in addition 3033 to signing the FIT image itself. This could be useful if you are 3034 intending to verify signatures in another context than booting via 3035 U-Boot. 3036 3037 This variable is set to "0" by default. 3038 3039 :term:`FIT_SIGN_NUMBITS` 3040 Size of the private key used in the FIT image, in number of bits. 3041 The default value for this variable is set to "2048" 3042 by the :ref:`ref-classes-kernel-fitimage` class. 3043 3044 :term:`FONT_EXTRA_RDEPENDS` 3045 When inheriting the :ref:`ref-classes-fontcache` class, 3046 this variable specifies the runtime dependencies for font packages. 3047 By default, the :term:`FONT_EXTRA_RDEPENDS` is set to "fontconfig-utils". 3048 3049 :term:`FONT_PACKAGES` 3050 When inheriting the :ref:`ref-classes-fontcache` class, this variable 3051 identifies packages containing font files that need to be cached by 3052 Fontconfig. By default, the :ref:`ref-classes-fontcache` class assumes 3053 that fonts are in the recipe's main package (i.e. 3054 ``${``\ :term:`PN`\ ``}``). Use this variable if fonts you 3055 need are in a package other than that main package. 3056 3057 :term:`FORCE_RO_REMOVE` 3058 Forces the removal of the packages listed in ``ROOTFS_RO_UNNEEDED`` 3059 during the generation of the root filesystem. 3060 3061 Set the variable to "1" to force the removal of these packages. 3062 3063 :term:`FULL_OPTIMIZATION` 3064 The options to pass in :term:`TARGET_CFLAGS` and :term:`CFLAGS` when 3065 compiling an optimized system. This variable defaults to "-O2 -pipe 3066 ${DEBUG_FLAGS}". 3067 3068 :term:`GCCPIE` 3069 Enables Position Independent Executables (PIE) within the GNU C 3070 Compiler (GCC). Enabling PIE in the GCC makes Return Oriented 3071 Programming (ROP) attacks much more difficult to execute. 3072 3073 By default the ``security_flags.inc`` file enables PIE by setting the 3074 variable as follows:: 3075 3076 GCCPIE ?= "--enable-default-pie" 3077 3078 :term:`GCCVERSION` 3079 Specifies the default version of the GNU C Compiler (GCC) used for 3080 compilation. By default, :term:`GCCVERSION` is set to "8.x" in the 3081 ``meta/conf/distro/include/tcmode-default.inc`` include file:: 3082 3083 GCCVERSION ?= "8.%" 3084 3085 You can override this value by setting it in a 3086 configuration file such as the ``local.conf``. 3087 3088 :term:`GDB` 3089 The minimal command and arguments to run the GNU Debugger. 3090 3091 :term:`GIR_EXTRA_LIBS_PATH` 3092 Allows to specify an extra search path for ``.so`` files 3093 in GLib related recipes using GObject introspection, 3094 and which do not compile without this setting. 3095 See the ":ref:`dev-manual/gobject-introspection:enabling gobject introspection support`" 3096 section for details. 3097 3098 :term:`GITDIR` 3099 The directory in which a local copy of a Git repository is stored 3100 when it is cloned. 3101 3102 :term:`GITHUB_BASE_URI` 3103 When inheriting the :ref:`ref-classes-github-releases` 3104 class, specifies the base URL for fetching releases for the github 3105 project you wish to fetch sources from. The default value is as follows:: 3106 3107 GITHUB_BASE_URI ?= "https://github.com/${BPN}/${BPN}/releases/" 3108 3109 :term:`GLIBC_GENERATE_LOCALES` 3110 Specifies the list of GLIBC locales to generate should you not wish 3111 to generate all LIBC locals, which can be time consuming. 3112 3113 .. note:: 3114 3115 If you specifically remove the locale ``en_US.UTF-8``, you must set 3116 :term:`IMAGE_LINGUAS` appropriately. 3117 3118 You can set :term:`GLIBC_GENERATE_LOCALES` in your ``local.conf`` file. 3119 By default, all locales are generated:: 3120 3121 GLIBC_GENERATE_LOCALES = "en_GB.UTF-8 en_US.UTF-8" 3122 3123 :term:`GO_IMPORT` 3124 When inheriting the :ref:`ref-classes-go` class, this mandatory variable 3125 sets the import path for the Go package that will be created for the code 3126 to build. If you have a ``go.mod`` file in the source directory, this 3127 typically matches the path in the ``module`` line in this file. 3128 3129 Other Go programs importing this package will use this path. 3130 3131 Here is an example setting from the 3132 :yocto_git:`go-helloworld_0.1.bb </poky/tree/meta/recipes-extended/go-examples/go-helloworld_0.1.bb>` 3133 recipe:: 3134 3135 GO_IMPORT = "golang.org/x/example" 3136 3137 :term:`GO_INSTALL` 3138 When inheriting the :ref:`ref-classes-go` class, this optional variable 3139 specifies which packages in the sources should be compiled and 3140 installed in the Go build space by the 3141 `go install <https://go.dev/ref/mod#go-install>`__ command. 3142 3143 Here is an example setting from the 3144 :oe_git:`crucible </meta-openembedded/tree/meta-oe/recipes-support/crucible/>` 3145 recipe:: 3146 3147 GO_INSTALL = "\ 3148 ${GO_IMPORT}/cmd/crucible \ 3149 ${GO_IMPORT}/cmd/habtool \ 3150 " 3151 3152 By default, :term:`GO_INSTALL` is defined as:: 3153 3154 GO_INSTALL ?= "${GO_IMPORT}/..." 3155 3156 The ``...`` wildcard means that it will catch all 3157 packages found in the sources. 3158 3159 See the :term:`GO_INSTALL_FILTEROUT` variable for 3160 filtering out unwanted packages from the ones 3161 found from the :term:`GO_INSTALL` value. 3162 3163 :term:`GO_INSTALL_FILTEROUT` 3164 When using the Go "vendor" mechanism to bring in dependencies for a Go 3165 package, the default :term:`GO_INSTALL` setting, which uses the ``...`` 3166 wildcard, will include the vendored packages in the build, which produces 3167 incorrect results. 3168 3169 There are also some Go packages that are structured poorly, so that the 3170 ``...`` wildcard results in building example or test code that should not 3171 be included in the build, or could fail to build. 3172 3173 This optional variable allows for filtering out a subset of the sources. 3174 It defaults to excluding everything under the ``vendor`` subdirectory 3175 under package's main directory. This is the normal location for vendored 3176 packages, but it can be overridden by a recipe to filter out other 3177 subdirectories if needed. 3178 3179 :term:`GO_WORKDIR` 3180 When using Go Modules, the current working directory must be the directory 3181 containing the ``go.mod`` file, or one of its subdirectories. When the 3182 ``go`` tool is used, it will automatically look for the ``go.mod`` file 3183 in the Go working directory or in any parent directory, but not in 3184 subdirectories. 3185 3186 When using the :ref:`ref-classes-go-mod` class to use Go modules, 3187 the optional :term:`GO_WORKDIR` variable, defaulting to the value 3188 of :term:`GO_IMPORT`, allows to specify a different Go working directory. 3189 3190 :term:`GROUPADD_PARAM` 3191 When inheriting the :ref:`ref-classes-useradd` class, 3192 this variable specifies for a package what parameters should be 3193 passed to the ``groupadd`` command if you wish to add a group to the 3194 system when the package is installed. 3195 3196 Here is an example from the ``dbus`` recipe:: 3197 3198 GROUPADD_PARAM:${PN} = "-r netdev" 3199 3200 For information on the standard Linux shell command 3201 ``groupadd``, see https://linux.die.net/man/8/groupadd. 3202 3203 :term:`GROUPMEMS_PARAM` 3204 When inheriting the :ref:`ref-classes-useradd` class, 3205 this variable specifies for a package what parameters should be 3206 passed to the ``groupmems`` command if you wish to modify the members 3207 of a group when the package is installed. 3208 3209 For information on the standard Linux shell command ``groupmems``, 3210 see https://linux.die.net/man/8/groupmems. 3211 3212 :term:`GRUB_GFXSERIAL` 3213 Configures the GNU GRand Unified Bootloader (GRUB) to have graphics 3214 and serial in the boot menu. Set this variable to "1" in your 3215 ``local.conf`` or distribution configuration file to enable graphics 3216 and serial in the menu. 3217 3218 See the :ref:`ref-classes-grub-efi` class for more 3219 information on how this variable is used. 3220 3221 :term:`GRUB_OPTS` 3222 Additional options to add to the GNU GRand Unified Bootloader (GRUB) 3223 configuration. Use a semi-colon character (``;``) to separate 3224 multiple options. 3225 3226 The :term:`GRUB_OPTS` variable is optional. See the 3227 :ref:`ref-classes-grub-efi` class for more information 3228 on how this variable is used. 3229 3230 :term:`GRUB_TIMEOUT` 3231 Specifies the timeout before executing the default ``LABEL`` in the 3232 GNU GRand Unified Bootloader (GRUB). 3233 3234 The :term:`GRUB_TIMEOUT` variable is optional. See the 3235 :ref:`ref-classes-grub-efi` class for more information 3236 on how this variable is used. 3237 3238 :term:`GTKIMMODULES_PACKAGES` 3239 When inheriting the :ref:`ref-classes-gtk-immodules-cache` class, 3240 this variable specifies the packages that contain the GTK+ input 3241 method modules being installed when the modules are in packages other 3242 than the main package. 3243 3244 :term:`HGDIR` 3245 See :term:`bitbake:HGDIR` in the BitBake manual. 3246 3247 :term:`HOMEPAGE` 3248 Website where more information about the software the recipe is 3249 building can be found. 3250 3251 :term:`HOST_ARCH` 3252 The name of the target architecture, which is normally the same as 3253 :term:`TARGET_ARCH`. The OpenEmbedded build system 3254 supports many architectures. Here is an example list of architectures 3255 supported. This list is by no means complete as the architecture is 3256 configurable: 3257 3258 - arm 3259 - i586 3260 - x86_64 3261 - powerpc 3262 - powerpc64 3263 - mips 3264 - mipsel 3265 3266 :term:`HOST_CC_ARCH` 3267 Specifies architecture-specific compiler flags that are passed to the 3268 C compiler. 3269 3270 Default initialization for :term:`HOST_CC_ARCH` varies depending on what 3271 is being built: 3272 3273 - :term:`TARGET_CC_ARCH` when building for the 3274 target 3275 3276 - :term:`BUILD_CC_ARCH` when building for the build host (i.e. 3277 ``-native``) 3278 3279 - ``BUILDSDK_CC_ARCH`` when building for an SDK (i.e. 3280 ``nativesdk-``) 3281 3282 :term:`HOST_OS` 3283 Specifies the name of the target operating system, which is normally 3284 the same as the :term:`TARGET_OS`. The variable can 3285 be set to "linux" for ``glibc``-based systems and to "linux-musl" for 3286 ``musl``. For ARM/EABI targets, there are also "linux-gnueabi" and 3287 "linux-musleabi" values possible. 3288 3289 :term:`HOST_PREFIX` 3290 Specifies the prefix for the cross-compile toolchain. :term:`HOST_PREFIX` 3291 is normally the same as :term:`TARGET_PREFIX`. 3292 3293 :term:`HOST_SYS` 3294 Specifies the system, including the architecture and the operating 3295 system, for which the build is occurring in the context of the 3296 current recipe. 3297 3298 The OpenEmbedded build system automatically sets this variable based 3299 on :term:`HOST_ARCH`, 3300 :term:`HOST_VENDOR`, and 3301 :term:`HOST_OS` variables. 3302 3303 .. note:: 3304 3305 You do not need to set the variable yourself. 3306 3307 Consider these two examples: 3308 3309 - Given a native recipe on a 32-bit x86 machine running Linux, the 3310 value is "i686-linux". 3311 3312 - Given a recipe being built for a little-endian MIPS target running 3313 Linux, the value might be "mipsel-linux". 3314 3315 :term:`HOST_VENDOR` 3316 Specifies the name of the vendor. :term:`HOST_VENDOR` is normally the 3317 same as :term:`TARGET_VENDOR`. 3318 3319 :term:`HOSTTOOLS` 3320 A space-separated list (filter) of tools on the build host that 3321 should be allowed to be called from within build tasks. Using this 3322 filter helps reduce the possibility of host contamination. If a tool 3323 specified in the value of :term:`HOSTTOOLS` is not found on the build 3324 host, the OpenEmbedded build system produces an error and the build 3325 is not started. 3326 3327 For additional information, see 3328 :term:`HOSTTOOLS_NONFATAL`. 3329 3330 :term:`HOSTTOOLS_NONFATAL` 3331 A space-separated list (filter) of tools on the build host that 3332 should be allowed to be called from within build tasks. Using this 3333 filter helps reduce the possibility of host contamination. Unlike 3334 :term:`HOSTTOOLS`, the OpenEmbedded build system 3335 does not produce an error if a tool specified in the value of 3336 :term:`HOSTTOOLS_NONFATAL` is not found on the build host. Thus, you can 3337 use :term:`HOSTTOOLS_NONFATAL` to filter optional host tools. 3338 3339 :term:`ICECC_CLASS_DISABLE` 3340 Identifies user classes that you do not want the Icecream distributed 3341 compile support to consider. This variable is used by the 3342 :ref:`ref-classes-icecc` class. You set this variable in 3343 your ``local.conf`` file. 3344 3345 When you list classes using this variable, the recipes inheriting 3346 those classes will not benefit from distributed compilation across 3347 remote hosts. Instead they will be built locally. 3348 3349 :term:`ICECC_DISABLED` 3350 Disables or enables the ``icecc`` (Icecream) function. For more 3351 information on this function and best practices for using this 3352 variable, see the ":ref:`ref-classes-icecc`" 3353 section. 3354 3355 Setting this variable to "1" in your ``local.conf`` disables the 3356 function:: 3357 3358 ICECC_DISABLED ??= "1" 3359 3360 To enable the function, set the variable as follows:: 3361 3362 ICECC_DISABLED = "" 3363 3364 :term:`ICECC_ENV_EXEC` 3365 Points to the ``icecc-create-env`` script that you provide. This 3366 variable is used by the :ref:`ref-classes-icecc` class. You 3367 set this variable in your ``local.conf`` file. 3368 3369 If you do not point to a script that you provide, the OpenEmbedded 3370 build system uses the default script provided by the 3371 :oe_git:`icecc-create-env_0.1.bb 3372 </openembedded-core/tree/meta/recipes-devtools/icecc-create-env/icecc-create-env_0.1.bb>` 3373 recipe, which is a modified version and not the one that comes with 3374 ``icecream``. 3375 3376 :term:`ICECC_PARALLEL_MAKE` 3377 Extra options passed to the ``make`` command during the 3378 :ref:`ref-tasks-compile` task that specify parallel 3379 compilation. This variable usually takes the form of "-j x", where x 3380 represents the maximum number of parallel threads ``make`` can run. 3381 3382 .. note:: 3383 3384 The options passed affect builds on all enabled machines on the 3385 network, which are machines running the ``iceccd`` daemon. 3386 3387 If your enabled machines support multiple cores, coming up with the 3388 maximum number of parallel threads that gives you the best 3389 performance could take some experimentation since machine speed, 3390 network lag, available memory, and existing machine loads can all 3391 affect build time. Consequently, unlike the 3392 :term:`PARALLEL_MAKE` variable, there is no 3393 rule-of-thumb for setting :term:`ICECC_PARALLEL_MAKE` to achieve optimal 3394 performance. 3395 3396 If you do not set :term:`ICECC_PARALLEL_MAKE`, the build system does not 3397 use it (i.e. the system does not detect and assign the number of 3398 cores as is done with :term:`PARALLEL_MAKE`). 3399 3400 :term:`ICECC_PATH` 3401 The location of the ``icecc`` binary. You can set this variable in 3402 your ``local.conf`` file. If your ``local.conf`` file does not define 3403 this variable, the :ref:`ref-classes-icecc` class attempts 3404 to define it by locating ``icecc`` using ``which``. 3405 3406 :term:`ICECC_RECIPE_DISABLE` 3407 Identifies user recipes that you do not want the Icecream distributed 3408 compile support to consider. This variable is used by the 3409 :ref:`ref-classes-icecc` class. You set this variable in 3410 your ``local.conf`` file. 3411 3412 When you list recipes using this variable, you are excluding them 3413 from distributed compilation across remote hosts. Instead they will 3414 be built locally. 3415 3416 :term:`ICECC_RECIPE_ENABLE` 3417 Identifies user recipes that use an empty 3418 :term:`PARALLEL_MAKE` variable that you want to 3419 force remote distributed compilation on using the Icecream 3420 distributed compile support. This variable is used by the 3421 :ref:`ref-classes-icecc` class. You set this variable in 3422 your ``local.conf`` file. 3423 3424 :term:`IMAGE_BASENAME` 3425 The base name of image output files. This variable defaults to the 3426 recipe name (``${``\ :term:`PN`\ ``}``). 3427 3428 :term:`IMAGE_BOOT_FILES` 3429 A space-separated list of files installed into the boot partition 3430 when preparing an image using the Wic tool with the 3431 ``bootimg-partition`` source plugin. By default, 3432 the files are 3433 installed under the same name as the source files. To change the 3434 installed name, separate it from the original name with a semi-colon 3435 (;). Source files need to be located in 3436 :term:`DEPLOY_DIR_IMAGE`. Here are two 3437 examples:: 3438 3439 IMAGE_BOOT_FILES = "u-boot.img uImage;kernel" 3440 IMAGE_BOOT_FILES = "u-boot.${UBOOT_SUFFIX} ${KERNEL_IMAGETYPE}" 3441 3442 Alternatively, source files can be picked up using a glob pattern. In 3443 this case, the destination file must have the same name as the base 3444 name of the source file path. To install files into a directory 3445 within the target location, pass its name after a semi-colon (;). 3446 Here are two examples:: 3447 3448 IMAGE_BOOT_FILES = "bcm2835-bootfiles/*" 3449 IMAGE_BOOT_FILES = "bcm2835-bootfiles/*;boot/" 3450 3451 The first example 3452 installs all files from ``${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles`` 3453 into the root of the target partition. The second example installs 3454 the same files into a ``boot`` directory within the target partition. 3455 3456 You can find information on how to use the Wic tool in the 3457 ":ref:`dev-manual/wic:creating partitioned images using wic`" 3458 section of the Yocto Project Development Tasks Manual. Reference 3459 material for Wic is located in the 3460 ":doc:`/ref-manual/kickstart`" chapter. 3461 3462 :term:`IMAGE_BUILDINFO_FILE` 3463 When using the :ref:`ref-classes-image-buildinfo` class, 3464 specifies the file in the image to write the build information into. The 3465 default value is "``${sysconfdir}/buildinfo``". 3466 3467 :term:`IMAGE_BUILDINFO_VARS` 3468 When using the :ref:`ref-classes-image-buildinfo` class, 3469 specifies the list of variables to include in the `Build Configuration` 3470 section of the output file (as a space-separated list). Defaults to 3471 ":term:`DISTRO` :term:`DISTRO_VERSION`". 3472 3473 :term:`IMAGE_CLASSES` 3474 A list of classes that all images should inherit. This is typically used 3475 to enable functionality across all image recipes. 3476 3477 Classes specified in :term:`IMAGE_CLASSES` must be located in the 3478 ``classes-recipe/`` or ``classes/`` subdirectories. 3479 3480 :term:`IMAGE_CMD` 3481 Specifies the command to create the image file for a specific image 3482 type, which corresponds to the value set in 3483 :term:`IMAGE_FSTYPES`, (e.g. ``ext3``, 3484 ``btrfs``, and so forth). When setting this variable, you should use 3485 an override for the associated type. Here is an example:: 3486 3487 IMAGE_CMD:jffs2 = "mkfs.jffs2 --root=${IMAGE_ROOTFS} --faketime \ 3488 --output=${IMGDEPLOYDIR}/${IMAGE_NAME}${IMAGE_NAME_SUFFIX}.jffs2 \ 3489 ${EXTRA_IMAGECMD}" 3490 3491 You typically do not need to set this variable unless you are adding 3492 support for a new image type. For more examples on how to set this 3493 variable, see the :ref:`ref-classes-image_types` 3494 class file, which is ``meta/classes-recipe/image_types.bbclass``. 3495 3496 :term:`IMAGE_DEVICE_TABLES` 3497 Specifies one or more files that contain custom device tables that 3498 are passed to the ``makedevs`` command as part of creating an image. 3499 These files list basic device nodes that should be created under 3500 ``/dev`` within the image. If :term:`IMAGE_DEVICE_TABLES` is not set, 3501 ``files/device_table-minimal.txt`` is used, which is located by 3502 :term:`BBPATH`. For details on how you should write 3503 device table files, see ``meta/files/device_table-minimal.txt`` as an 3504 example. 3505 3506 :term:`IMAGE_EFI_BOOT_FILES` 3507 A space-separated list of files installed into the boot partition 3508 when preparing an image using the Wic tool with the 3509 ``bootimg-efi`` source plugin. By default, 3510 the files are 3511 installed under the same name as the source files. To change the 3512 installed name, separate it from the original name with a semi-colon 3513 (;). Source files need to be located in 3514 :term:`DEPLOY_DIR_IMAGE`. Here are two 3515 examples:: 3516 3517 IMAGE_EFI_BOOT_FILES = "${KERNEL_IMAGETYPE};bz2" 3518 IMAGE_EFI_BOOT_FILES = "${KERNEL_IMAGETYPE} microcode.cpio" 3519 3520 Alternatively, source files can be picked up using a glob pattern. In 3521 this case, the destination file must have the same name as the base 3522 name of the source file path. To install files into a directory 3523 within the target location, pass its name after a semi-colon (;). 3524 Here are two examples:: 3525 3526 IMAGE_EFI_BOOT_FILES = "boot/loader/*" 3527 IMAGE_EFI_BOOT_FILES = "boot/loader/*;boot/" 3528 3529 The first example 3530 installs all files from ``${DEPLOY_DIR_IMAGE}/boot/loader/`` 3531 into the root of the target partition. The second example installs 3532 the same files into a ``boot`` directory within the target partition. 3533 3534 You can find information on how to use the Wic tool in the 3535 ":ref:`dev-manual/wic:creating partitioned images using wic`" 3536 section of the Yocto Project Development Tasks Manual. Reference 3537 material for Wic is located in the 3538 ":doc:`/ref-manual/kickstart`" chapter. 3539 3540 :term:`IMAGE_FEATURES` 3541 The primary list of features to include in an image. Typically, you 3542 configure this variable in an image recipe. Although you can use this 3543 variable from your ``local.conf`` file, which is found in the 3544 :term:`Build Directory`, best practices dictate that you do 3545 not. 3546 3547 .. note:: 3548 3549 To enable extra features from outside the image recipe, use the 3550 :term:`EXTRA_IMAGE_FEATURES` variable. 3551 3552 For a list of image features that ships with the Yocto Project, see 3553 the ":ref:`ref-features-image`" section. 3554 3555 For an example that shows how to customize your image by using this 3556 variable, see the ":ref:`dev-manual/customizing-images:customizing images using custom \`\`image_features\`\` and \`\`extra_image_features\`\``" 3557 section in the Yocto Project Development Tasks Manual. 3558 3559 :term:`IMAGE_FSTYPES` 3560 Specifies the formats the OpenEmbedded build system uses during the 3561 build when creating the root filesystem. For example, setting 3562 :term:`IMAGE_FSTYPES` as follows causes the build system to create root 3563 filesystems using two formats: ``.ext3`` and ``.tar.bz2``:: 3564 3565 IMAGE_FSTYPES = "ext3 tar.bz2" 3566 3567 For the complete list of supported image formats from which you can 3568 choose, see :term:`IMAGE_TYPES`. 3569 3570 .. note:: 3571 3572 - If an image recipe uses the "inherit image" line and you are 3573 setting :term:`IMAGE_FSTYPES` inside the recipe, you must set 3574 :term:`IMAGE_FSTYPES` prior to using the "inherit image" line. 3575 3576 - Due to the way the OpenEmbedded build system processes this 3577 variable, you cannot update its contents by using ``:append`` 3578 or ``:prepend``. You must use the ``+=`` operator to add one or 3579 more options to the :term:`IMAGE_FSTYPES` variable. 3580 3581 :term:`IMAGE_INSTALL` 3582 Used by recipes to specify the packages to install into an image 3583 through the :ref:`ref-classes-image` class. Use the 3584 :term:`IMAGE_INSTALL` variable with care to avoid ordering issues. 3585 3586 Image recipes set :term:`IMAGE_INSTALL` to specify the packages to 3587 install into an image through :ref:`ref-classes-image`. Additionally, 3588 there are "helper" classes such as the :ref:`ref-classes-core-image` 3589 class which can take lists used with :term:`IMAGE_FEATURES` and turn 3590 them into auto-generated entries in :term:`IMAGE_INSTALL` in addition 3591 to its default contents. 3592 3593 When you use this variable, it is best to use it as follows:: 3594 3595 IMAGE_INSTALL:append = " package-name" 3596 3597 Be sure to include the space 3598 between the quotation character and the start of the package name or 3599 names. 3600 3601 .. note:: 3602 3603 - When working with a 3604 :ref:`core-image-minimal-initramfs <ref-manual/images:images>` 3605 image, do not use the :term:`IMAGE_INSTALL` variable to specify 3606 packages for installation. Instead, use the 3607 :term:`PACKAGE_INSTALL` variable, which 3608 allows the initial RAM filesystem (:term:`Initramfs`) recipe to use a 3609 fixed set of packages and not be affected by :term:`IMAGE_INSTALL`. 3610 For information on creating an :term:`Initramfs`, see the 3611 ":ref:`dev-manual/building:building an initial ram filesystem (Initramfs) image`" 3612 section in the Yocto Project Development Tasks Manual. 3613 3614 - Using :term:`IMAGE_INSTALL` with the 3615 :ref:`+= <bitbake-user-manual/bitbake-user-manual-metadata:appending (+=) and prepending (=+) with spaces>` 3616 BitBake operator within the ``/conf/local.conf`` file or from 3617 within an image recipe is not recommended. Use of this operator in 3618 these ways can cause ordering issues. Since 3619 :ref:`ref-classes-core-image` sets :term:`IMAGE_INSTALL` to a 3620 default value using the 3621 :ref:`?= <bitbake-user-manual/bitbake-user-manual-metadata:setting a default value (?=)>` 3622 operator, using a ``+=`` operation against :term:`IMAGE_INSTALL` 3623 results in unexpected behavior when used within 3624 ``conf/local.conf``. Furthermore, the same operation from within an 3625 image recipe may or may not succeed depending on the specific 3626 situation. In both these cases, the behavior is contrary to how 3627 most users expect the ``+=`` operator to work. 3628 3629 :term:`IMAGE_LINGUAS` 3630 Specifies the list of locales to install into the image during the 3631 root filesystem construction process. The OpenEmbedded build system 3632 automatically splits locale files, which are used for localization, 3633 into separate packages. Setting the :term:`IMAGE_LINGUAS` variable 3634 ensures that any locale packages that correspond to packages already 3635 selected for installation into the image are also installed. Here is 3636 an example:: 3637 3638 IMAGE_LINGUAS = "pt-br de-de" 3639 3640 In this example, the build system ensures any Brazilian Portuguese 3641 and German locale files that correspond to packages in the image are 3642 installed (i.e. ``*-locale-pt-br`` and ``*-locale-de-de`` as well as 3643 ``*-locale-pt`` and ``*-locale-de``, since some software packages 3644 only provide locale files by language and not by country-specific 3645 language). 3646 3647 See the :term:`GLIBC_GENERATE_LOCALES` 3648 variable for information on generating GLIBC locales. 3649 3650 3651 :term:`IMAGE_LINK_NAME` 3652 The name of the output image symlink (which does not include 3653 the version part as :term:`IMAGE_NAME` does). The default value 3654 is derived using the :term:`IMAGE_BASENAME` and 3655 :term:`IMAGE_MACHINE_SUFFIX` variables:: 3656 3657 IMAGE_LINK_NAME ?= "${IMAGE_BASENAME}${IMAGE_MACHINE_SUFFIX}" 3658 3659 .. note:: 3660 3661 It is possible to set this to "" to disable symlink creation, 3662 however, you also need to set :term:`IMAGE_NAME` to still have 3663 a reasonable value e.g.:: 3664 3665 IMAGE_LINK_NAME = "" 3666 IMAGE_NAME = "${IMAGE_BASENAME}${IMAGE_MACHINE_SUFFIX}${IMAGE_VERSION_SUFFIX}" 3667 3668 :term:`IMAGE_MACHINE_SUFFIX` 3669 Specifies the by default machine-specific suffix for image file names 3670 (before the extension). The default value is set as follows:: 3671 3672 IMAGE_MACHINE_SUFFIX ??= "-${MACHINE}" 3673 3674 The default :term:`DEPLOY_DIR_IMAGE` already has a :term:`MACHINE` 3675 subdirectory, so you may find it unnecessary to also include this suffix 3676 in the name of every image file. If you prefer to remove the suffix you 3677 can set this variable to an empty string:: 3678 3679 IMAGE_MACHINE_SUFFIX = "" 3680 3681 (Not to be confused with :term:`IMAGE_NAME_SUFFIX`.) 3682 3683 :term:`IMAGE_MANIFEST` 3684 The manifest file for the image. This file lists all the installed 3685 packages that make up the image. The file contains package 3686 information on a line-per-package basis as follows:: 3687 3688 packagename packagearch version 3689 3690 The :ref:`rootfs-postcommands <ref-classes-rootfs*>` class defines the manifest 3691 file as follows:: 3692 3693 IMAGE_MANIFEST ="${IMGDEPLOYDIR}/${IMAGE_NAME}${IMAGE_NAME_SUFFIX}.manifest" 3694 3695 The location is 3696 derived using the :term:`IMGDEPLOYDIR` 3697 and :term:`IMAGE_NAME` variables. You can find 3698 information on how the image is created in the ":ref:`overview-manual/concepts:image generation`" 3699 section in the Yocto Project Overview and Concepts Manual. 3700 3701 :term:`IMAGE_NAME` 3702 The name of the output image files minus the extension. By default 3703 this variable is set using the :term:`IMAGE_LINK_NAME`, and 3704 :term:`IMAGE_VERSION_SUFFIX` variables:: 3705 3706 IMAGE_NAME ?= "${IMAGE_LINK_NAME}${IMAGE_VERSION_SUFFIX}" 3707 3708 :term:`IMAGE_NAME_SUFFIX` 3709 Suffix used for the image output filename --- defaults to ``".rootfs"`` 3710 to distinguish the image file from other files created during image 3711 building; however if this suffix is redundant or not desired you can 3712 clear the value of this variable (set the value to ""). For example, 3713 this is typically cleared in :term:`Initramfs` image recipes. 3714 3715 :term:`IMAGE_OVERHEAD_FACTOR` 3716 Defines a multiplier that the build system applies to the initial 3717 image size for cases when the multiplier times the returned disk 3718 usage value for the image is greater than the sum of 3719 :term:`IMAGE_ROOTFS_SIZE` and :term:`IMAGE_ROOTFS_EXTRA_SPACE`. The result of 3720 the multiplier applied to the initial image size creates free disk 3721 space in the image as overhead. By default, the build process uses a 3722 multiplier of 1.3 for this variable. This default value results in 3723 30% free disk space added to the image when this method is used to 3724 determine the final generated image size. You should be aware that 3725 post install scripts and the package management system uses disk 3726 space inside this overhead area. Consequently, the multiplier does 3727 not produce an image with all the theoretical free disk space. See 3728 :term:`IMAGE_ROOTFS_SIZE` for information on how the build system 3729 determines the overall image size. 3730 3731 The default 30% free disk space typically gives the image enough room 3732 to boot and allows for basic post installs while still leaving a 3733 small amount of free disk space. If 30% free space is inadequate, you 3734 can increase the default value. For example, the following setting 3735 gives you 50% free space added to the image:: 3736 3737 IMAGE_OVERHEAD_FACTOR = "1.5" 3738 3739 Alternatively, you can ensure a specific amount of free disk space is 3740 added to the image by using the :term:`IMAGE_ROOTFS_EXTRA_SPACE` 3741 variable. 3742 3743 :term:`IMAGE_PKGTYPE` 3744 Defines the package type (i.e. DEB, RPM, IPK, or TAR) used by the 3745 OpenEmbedded build system. The variable is defined appropriately by 3746 the :ref:`ref-classes-package_deb`, :ref:`ref-classes-package_rpm`, 3747 or :ref:`ref-classes-package_ipk` class. 3748 3749 The :ref:`ref-classes-populate-sdk-*` and :ref:`ref-classes-image` 3750 classes use the :term:`IMAGE_PKGTYPE` for packaging up images and SDKs. 3751 3752 You should not set the :term:`IMAGE_PKGTYPE` manually. Rather, the 3753 variable is set indirectly through the appropriate 3754 :ref:`package_* <ref-classes-package>` class using the 3755 :term:`PACKAGE_CLASSES` variable. The 3756 OpenEmbedded build system uses the first package type (e.g. DEB, RPM, 3757 or IPK) that appears with the variable 3758 3759 .. note:: 3760 3761 Files using the ``.tar`` format are never used as a substitute 3762 packaging format for DEB, RPM, and IPK formatted files for your image 3763 or SDK. 3764 3765 :term:`IMAGE_POSTPROCESS_COMMAND` 3766 Specifies a list of functions to call once the OpenEmbedded build 3767 system creates the final image output files. You can specify 3768 functions separated by semicolons:: 3769 3770 IMAGE_POSTPROCESS_COMMAND += "function; ... " 3771 3772 If you need to pass the root filesystem path to a command within the 3773 function, you can use ``${IMAGE_ROOTFS}``, which points to the 3774 directory that becomes the root filesystem image. See the 3775 :term:`IMAGE_ROOTFS` variable for more 3776 information. 3777 3778 :term:`IMAGE_PREPROCESS_COMMAND` 3779 Specifies a list of functions to call before the OpenEmbedded build 3780 system creates the final image output files. You can specify 3781 functions separated by semicolons:: 3782 3783 IMAGE_PREPROCESS_COMMAND += "function; ... " 3784 3785 If you need to pass the root filesystem path to a command within the 3786 function, you can use ``${IMAGE_ROOTFS}``, which points to the 3787 directory that becomes the root filesystem image. See the 3788 :term:`IMAGE_ROOTFS` variable for more 3789 information. 3790 3791 :term:`IMAGE_ROOTFS` 3792 The location of the root filesystem while it is under construction 3793 (i.e. during the :ref:`ref-tasks-rootfs` task). This 3794 variable is not configurable. Do not change it. 3795 3796 :term:`IMAGE_ROOTFS_ALIGNMENT` 3797 Specifies the alignment for the output image file in Kbytes. If the 3798 size of the image is not a multiple of this value, then the size is 3799 rounded up to the nearest multiple of the value. The default value is 3800 "1". See :term:`IMAGE_ROOTFS_SIZE` for 3801 additional information. 3802 3803 :term:`IMAGE_ROOTFS_EXTRA_SPACE` 3804 Defines additional free disk space created in the image in Kbytes. By 3805 default, this variable is set to "0". This free disk space is added 3806 to the image after the build system determines the image size as 3807 described in :term:`IMAGE_ROOTFS_SIZE`. 3808 3809 This variable is particularly useful when you want to ensure that a 3810 specific amount of free disk space is available on a device after an 3811 image is installed and running. For example, to be sure 5 Gbytes of 3812 free disk space is available, set the variable as follows:: 3813 3814 IMAGE_ROOTFS_EXTRA_SPACE = "5242880" 3815 3816 For example, the Yocto Project Build Appliance specifically requests 3817 40 Gbytes of extra space with the line:: 3818 3819 IMAGE_ROOTFS_EXTRA_SPACE = "41943040" 3820 3821 :term:`IMAGE_ROOTFS_SIZE` 3822 Defines the size in Kbytes for the generated image. The OpenEmbedded 3823 build system determines the final size for the generated image using 3824 an algorithm that takes into account the initial disk space used for 3825 the generated image, a requested size for the image, and requested 3826 additional free disk space to be added to the image. Programatically, 3827 the build system determines the final size of the generated image as 3828 follows:: 3829 3830 if (image-du * overhead) < rootfs-size: 3831 internal-rootfs-size = rootfs-size + xspace 3832 else: 3833 internal-rootfs-size = (image-du * overhead) + xspace 3834 where: 3835 image-du = Returned value of the du command on the image. 3836 overhead = IMAGE_OVERHEAD_FACTOR 3837 rootfs-size = IMAGE_ROOTFS_SIZE 3838 internal-rootfs-size = Initial root filesystem size before any modifications. 3839 xspace = IMAGE_ROOTFS_EXTRA_SPACE 3840 3841 See the :term:`IMAGE_OVERHEAD_FACTOR` 3842 and :term:`IMAGE_ROOTFS_EXTRA_SPACE` 3843 variables for related information. 3844 3845 :term:`IMAGE_TYPEDEP` 3846 Specifies a dependency from one image type on another. Here is an 3847 example from the :ref:`ref-classes-image-live` class:: 3848 3849 IMAGE_TYPEDEP:live = "ext3" 3850 3851 In the previous example, the variable ensures that when "live" is 3852 listed with the :term:`IMAGE_FSTYPES` variable, 3853 the OpenEmbedded build system produces an ``ext3`` image first since 3854 one of the components of the live image is an ``ext3`` formatted 3855 partition containing the root filesystem. 3856 3857 :term:`IMAGE_TYPES` 3858 Specifies the complete list of supported image types by default: 3859 3860 - btrfs 3861 - container 3862 - cpio 3863 - cpio.gz 3864 - cpio.lz4 3865 - cpio.lzma 3866 - cpio.xz 3867 - cramfs 3868 - erofs 3869 - erofs-lz4 3870 - erofs-lz4hc 3871 - ext2 3872 - ext2.bz2 3873 - ext2.gz 3874 - ext2.lzma 3875 - ext3 3876 - ext3.gz 3877 - ext4 3878 - ext4.gz 3879 - f2fs 3880 - hddimg 3881 - iso 3882 - jffs2 3883 - jffs2.sum 3884 - multiubi 3885 - squashfs 3886 - squashfs-lz4 3887 - squashfs-lzo 3888 - squashfs-xz 3889 - tar 3890 - tar.bz2 3891 - tar.gz 3892 - tar.lz4 3893 - tar.xz 3894 - tar.zst 3895 - ubi 3896 - ubifs 3897 - wic 3898 - wic.bz2 3899 - wic.gz 3900 - wic.lzma 3901 3902 For more information about these types of images, see 3903 ``meta/classes-recipe/image_types*.bbclass`` in the :term:`Source Directory`. 3904 3905 :term:`IMAGE_VERSION_SUFFIX` 3906 Version suffix that is part of the default :term:`IMAGE_NAME` and 3907 :term:`KERNEL_ARTIFACT_NAME` values. 3908 Defaults to ``"-${DATETIME}"``, however you could set this to a 3909 version string that comes from your external build environment if 3910 desired, and this suffix would then be used consistently across 3911 the build artifacts. 3912 3913 :term:`IMGDEPLOYDIR` 3914 When inheriting the :ref:`ref-classes-image` class directly or 3915 through the :ref:`ref-classes-core-image` class, the 3916 :term:`IMGDEPLOYDIR` points to a temporary work area for deployed files 3917 that is set in the ``image`` class as follows:: 3918 3919 IMGDEPLOYDIR = "${WORKDIR}/deploy-${PN}-image-complete" 3920 3921 Recipes inheriting the :ref:`ref-classes-image` class should copy 3922 files to be deployed into :term:`IMGDEPLOYDIR`, and the class will take 3923 care of copying them into :term:`DEPLOY_DIR_IMAGE` afterwards. 3924 3925 :term:`INCOMPATIBLE_LICENSE` 3926 Specifies a space-separated list of license names (as they would 3927 appear in :term:`LICENSE`) that should be excluded 3928 from the build (if set globally), or from an image (if set locally 3929 in an image recipe). 3930 3931 When the variable is set globally, recipes that provide no alternatives to listed 3932 incompatible licenses are not built. Packages that are individually 3933 licensed with the specified incompatible licenses will be deleted. 3934 Most of the time this does not allow a feasible build (because it becomes impossible 3935 to satisfy build time dependencies), so the recommended way to 3936 implement license restrictions is to set the variable in specific 3937 image recipes where the restrictions must apply. That way there 3938 are no build time restrictions, but the license check is still 3939 performed when the image's filesystem is assembled from packages. 3940 3941 There is some support for wildcards in this variable's value, 3942 however it is restricted to specific licenses. Currently only 3943 these wildcards are allowed and expand as follows: 3944 3945 - ``AGPL-3.0*"``: ``AGPL-3.0-only``, ``AGPL-3.0-or-later`` 3946 - ``GPL-3.0*``: ``GPL-3.0-only``, ``GPL-3.0-or-later`` 3947 - ``LGPL-3.0*``: ``LGPL-3.0-only``, ``LGPL-3.0-or-later`` 3948 3949 .. note:: 3950 3951 This functionality is only regularly tested using the following 3952 setting:: 3953 3954 INCOMPATIBLE_LICENSE = "GPL-3.0* LGPL-3.0* AGPL-3.0*" 3955 3956 3957 Although you can use other settings, you might be required to 3958 remove dependencies on (or provide alternatives to) components that 3959 are required to produce a functional system image. 3960 3961 :term:`INCOMPATIBLE_LICENSE_EXCEPTIONS` 3962 Specifies a space-separated list of package and license pairs that 3963 are allowed to be used even if the license is specified in 3964 :term:`INCOMPATIBLE_LICENSE`. The package and license pairs are 3965 separated using a colon. Example:: 3966 3967 INCOMPATIBLE_LICENSE_EXCEPTIONS = "gdbserver:GPL-3.0-only gdbserver:LGPL-3.0-only" 3968 3969 :term:`INHERIT` 3970 Causes the named class or classes to be inherited globally. Anonymous 3971 functions in the class or classes are not executed for the base 3972 configuration and in each individual recipe. The OpenEmbedded build 3973 system ignores changes to :term:`INHERIT` in individual recipes. 3974 Classes inherited using :term:`INHERIT` must be located in the 3975 ``classes-global/`` or ``classes/`` subdirectories. 3976 3977 For more information on :term:`INHERIT`, see the 3978 :ref:`bitbake-user-manual/bitbake-user-manual-metadata:\`\`inherit\`\` configuration directive`" 3979 section in the BitBake User Manual. 3980 3981 :term:`INHERIT_DISTRO` 3982 Lists classes that will be inherited at the distribution level. It is 3983 unlikely that you want to edit this variable. 3984 3985 Classes specified in :term:`INHERIT_DISTRO` must be located in the 3986 ``classes-global/`` or ``classes/`` subdirectories. 3987 3988 The default value of the variable is set as follows in the 3989 ``meta/conf/distro/defaultsetup.conf`` file:: 3990 3991 INHERIT_DISTRO ?= "debian devshell sstate license" 3992 3993 :term:`INHIBIT_DEFAULT_DEPS` 3994 Prevents the default dependencies, namely the C compiler and standard 3995 C library (libc), from being added to :term:`DEPENDS`. 3996 This variable is usually used within recipes that do not require any 3997 compilation using the C compiler. 3998 3999 Set the variable to "1" to prevent the default dependencies from 4000 being added. 4001 4002 :term:`INHIBIT_PACKAGE_DEBUG_SPLIT` 4003 Prevents the OpenEmbedded build system from splitting out debug 4004 information during packaging. By default, the build system splits out 4005 debugging information during the 4006 :ref:`ref-tasks-package` task. For more information on 4007 how debug information is split out, see the 4008 :term:`PACKAGE_DEBUG_SPLIT_STYLE` 4009 variable. 4010 4011 To prevent the build system from splitting out debug information 4012 during packaging, set the :term:`INHIBIT_PACKAGE_DEBUG_SPLIT` variable as 4013 follows:: 4014 4015 INHIBIT_PACKAGE_DEBUG_SPLIT = "1" 4016 4017 :term:`INHIBIT_PACKAGE_STRIP` 4018 If set to "1", causes the build to not strip binaries in resulting 4019 packages and prevents the ``-dbg`` package from containing the source 4020 files. 4021 4022 By default, the OpenEmbedded build system strips binaries and puts 4023 the debugging symbols into ``${``\ :term:`PN`\ ``}-dbg``. 4024 Consequently, you should not set :term:`INHIBIT_PACKAGE_STRIP` when you 4025 plan to debug in general. 4026 4027 :term:`INHIBIT_SYSROOT_STRIP` 4028 If set to "1", causes the build to not strip binaries in the 4029 resulting sysroot. 4030 4031 By default, the OpenEmbedded build system strips binaries in the 4032 resulting sysroot. When you specifically set the 4033 :term:`INHIBIT_SYSROOT_STRIP` variable to "1" in your recipe, you inhibit 4034 this stripping. 4035 4036 If you want to use this variable, include the :ref:`ref-classes-staging` 4037 class. This class uses a ``sys_strip()`` function to test for the variable 4038 and acts accordingly. 4039 4040 .. note:: 4041 4042 Use of the :term:`INHIBIT_SYSROOT_STRIP` variable occurs in rare and 4043 special circumstances. For example, suppose you are building 4044 bare-metal firmware by using an external GCC toolchain. Furthermore, 4045 even if the toolchain's binaries are strippable, there are other files 4046 needed for the build that are not strippable. 4047 4048 :term:`INIT_MANAGER` 4049 Specifies the system init manager to use. Available options are: 4050 4051 - ``sysvinit`` 4052 - ``systemd`` 4053 - ``mdev-busybox`` 4054 4055 With ``sysvinit``, the init manager is set to 4056 :wikipedia:`SysVinit <Init#SysV-style>`, the traditional UNIX init 4057 system. This is the default choice in the Poky distribution, together with 4058 the Udev device manager (see the ":ref:`device-manager`" section). 4059 4060 With ``systemd``, the init manager becomes :wikipedia:`systemd <Systemd>`, 4061 which comes with the :wikipedia:`udev <Udev>` device manager. 4062 4063 With ``mdev-busybox``, the init manager becomes the much simpler BusyBox 4064 init, together with the BusyBox mdev device manager. This is the simplest 4065 and lightest solution, and probably the best choice for low-end systems 4066 with a rather slow CPU and a limited amount of RAM. 4067 4068 More concretely, this is used to include 4069 ``conf/distro/include/init-manager-${INIT_MANAGER}.inc`` into the global 4070 configuration. You can have a look at the 4071 :yocto_git:`meta/conf/distro/include/init-manager-*.inc </poky/tree/meta/conf/distro/include>` 4072 files for more information, and also the ":ref:`init-manager`" 4073 section in the Yocto Project Development Tasks Manual. 4074 4075 :term:`INITRAMFS_DEPLOY_DIR_IMAGE` 4076 Indicates the deploy directory used by :ref:`ref-tasks-bundle_initramfs` 4077 where the :term:`INITRAMFS_IMAGE` will be fetched from. This variable is 4078 set by default to ``${DEPLOY_DIR_IMAGE}`` in the 4079 :ref:`ref-classes-kernel` class and it's only meant to be changed when 4080 building an :term:`Initramfs` image from a separate multiconfig via 4081 :term:`INITRAMFS_MULTICONFIG`. 4082 4083 :term:`INITRAMFS_FSTYPES` 4084 Defines the format for the output image of an initial RAM filesystem 4085 (:term:`Initramfs`), which is used during boot. Supported formats are the 4086 same as those supported by the 4087 :term:`IMAGE_FSTYPES` variable. 4088 4089 The default value of this variable, which is set in the 4090 ``meta/conf/bitbake.conf`` configuration file in the 4091 :term:`Source Directory`, is "cpio.gz". The Linux kernel's 4092 :term:`Initramfs` mechanism, as opposed to the initial RAM filesystem 4093 :wikipedia:`initrd <Initrd>` mechanism, expects 4094 an optionally compressed cpio archive. 4095 4096 :term:`INITRAMFS_IMAGE` 4097 Specifies the :term:`PROVIDES` name of an image 4098 recipe that is used to build an initial RAM filesystem (:term:`Initramfs`) 4099 image. In other words, the :term:`INITRAMFS_IMAGE` variable causes an 4100 additional recipe to be built as a dependency to whatever root 4101 filesystem recipe you might be using (e.g. ``core-image-sato``). The 4102 :term:`Initramfs` image recipe you provide should set 4103 :term:`IMAGE_FSTYPES` to 4104 :term:`INITRAMFS_FSTYPES`. 4105 4106 An :term:`Initramfs` image provides a temporary root filesystem used for 4107 early system initialization (e.g. loading of modules needed to locate 4108 and mount the "real" root filesystem). 4109 4110 .. note:: 4111 4112 See the ``meta/recipes-core/images/core-image-minimal-initramfs.bb`` 4113 recipe in the :term:`Source Directory` 4114 for an example :term:`Initramfs` recipe. To select this sample recipe as 4115 the one built to provide the :term:`Initramfs` image, set :term:`INITRAMFS_IMAGE` 4116 to "core-image-minimal-initramfs". 4117 4118 You can also find more information by referencing the 4119 ``meta-poky/conf/templates/default/local.conf.sample.extended`` 4120 configuration file in the Source Directory, the :ref:`ref-classes-image` 4121 class, and the :ref:`ref-classes-kernel` class to see how to use the 4122 :term:`INITRAMFS_IMAGE` variable. 4123 4124 If :term:`INITRAMFS_IMAGE` is empty, which is the default, then no 4125 :term:`Initramfs` image is built. 4126 4127 For more information, you can also see the 4128 :term:`INITRAMFS_IMAGE_BUNDLE` 4129 variable, which allows the generated image to be bundled inside the 4130 kernel image. Additionally, for information on creating an :term:`Initramfs` 4131 image, see the ":ref:`dev-manual/building:building an initial ram filesystem (Initramfs) image`" section 4132 in the Yocto Project Development Tasks Manual. 4133 4134 :term:`INITRAMFS_IMAGE_BUNDLE` 4135 Controls whether or not the image recipe specified by 4136 :term:`INITRAMFS_IMAGE` is run through an 4137 extra pass 4138 (:ref:`ref-tasks-bundle_initramfs`) during 4139 kernel compilation in order to build a single binary that contains 4140 both the kernel image and the initial RAM filesystem (:term:`Initramfs`) 4141 image. This makes use of the 4142 :term:`CONFIG_INITRAMFS_SOURCE` kernel 4143 feature. 4144 4145 .. note:: 4146 4147 Bundling the :term:`Initramfs` with the kernel conflates the code in the 4148 :term:`Initramfs` with the GPLv2 licensed Linux kernel binary. Thus only GPLv2 4149 compatible software may be part of a bundled :term:`Initramfs`. 4150 4151 .. note:: 4152 4153 Using an extra compilation pass to bundle the :term:`Initramfs` avoids a 4154 circular dependency between the kernel recipe and the :term:`Initramfs` 4155 recipe should the :term:`Initramfs` include kernel modules. Should that be 4156 the case, the :term:`Initramfs` recipe depends on the kernel for the 4157 kernel modules, and the kernel depends on the :term:`Initramfs` recipe 4158 since the :term:`Initramfs` is bundled inside the kernel image. 4159 4160 The combined binary is deposited into the ``tmp/deploy`` directory, 4161 which is part of the :term:`Build Directory`. 4162 4163 Setting the variable to "1" in a configuration file causes the 4164 OpenEmbedded build system to generate a kernel image with the 4165 :term:`Initramfs` specified in :term:`INITRAMFS_IMAGE` bundled within:: 4166 4167 INITRAMFS_IMAGE_BUNDLE = "1" 4168 4169 By default, the :ref:`ref-classes-kernel` class sets this variable to a 4170 null string as follows:: 4171 4172 INITRAMFS_IMAGE_BUNDLE ?= "" 4173 4174 .. note:: 4175 4176 You must set the :term:`INITRAMFS_IMAGE_BUNDLE` variable in a 4177 configuration file. You cannot set the variable in a recipe file. 4178 4179 See the 4180 :yocto_git:`local.conf.sample.extended </poky/tree/meta-poky/conf/templates/default/local.conf.sample.extended>` 4181 file for additional information. Also, for information on creating an 4182 :term:`Initramfs`, see the ":ref:`dev-manual/building:building an initial ram filesystem (Initramfs) image`" section 4183 in the Yocto Project Development Tasks Manual. 4184 4185 :term:`INITRAMFS_IMAGE_NAME` 4186 4187 This value needs to stay in sync with :term:`IMAGE_LINK_NAME`, but with 4188 :term:`INITRAMFS_IMAGE` instead of :term:`IMAGE_BASENAME`. The default value 4189 is set as follows: 4190 4191 INITRAMFS_IMAGE_NAME ?= "${@['${INITRAMFS_IMAGE}${IMAGE_MACHINE_SUFFIX}', ''][d.getVar('INITRAMFS_IMAGE') == '']}" 4192 4193 That is, if :term:`INITRAMFS_IMAGE` is set, the value of 4194 :term:`INITRAMFS_IMAGE_NAME` will be set based upon 4195 :term:`INITRAMFS_IMAGE` and :term:`IMAGE_MACHINE_SUFFIX`. 4196 4197 4198 :term:`INITRAMFS_LINK_NAME` 4199 The link name of the initial RAM filesystem image. This variable is 4200 set in the ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as 4201 follows:: 4202 4203 INITRAMFS_LINK_NAME ?= "initramfs-${KERNEL_ARTIFACT_LINK_NAME}" 4204 4205 The value of the 4206 ``KERNEL_ARTIFACT_LINK_NAME`` variable, which is set in the same 4207 file, has the following value:: 4208 4209 KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}" 4210 4211 See the :term:`MACHINE` variable for additional 4212 information. 4213 4214 :term:`INITRAMFS_MULTICONFIG` 4215 Defines the multiconfig to create a multiconfig dependency to be used by 4216 the :ref:`ref-classes-kernel` class. 4217 4218 This allows the kernel to bundle an :term:`INITRAMFS_IMAGE` coming from 4219 a separate multiconfig, this is meant to be used in addition to :term:`INITRAMFS_DEPLOY_DIR_IMAGE`. 4220 4221 For more information on how to bundle an :term:`Initramfs` image from a separate 4222 multiconfig see the ":ref:`dev-manual/building:Bundling an Initramfs Image From a Separate Multiconfig`" 4223 section in the Yocto Project Development Tasks Manual. 4224 4225 :term:`INITRAMFS_NAME` 4226 The base name of the initial RAM filesystem image. This variable is 4227 set in the ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as 4228 follows:: 4229 4230 INITRAMFS_NAME ?= "initramfs-${KERNEL_ARTIFACT_NAME}" 4231 4232 See :term:`KERNEL_ARTIFACT_NAME` for additional information. 4233 4234 :term:`INITRD` 4235 Indicates list of filesystem images to concatenate and use as an 4236 initial RAM disk (``initrd``). 4237 4238 The :term:`INITRD` variable is an optional variable used with the 4239 :ref:`ref-classes-image-live` class. 4240 4241 :term:`INITRD_IMAGE` 4242 When building a "live" bootable image (i.e. when 4243 :term:`IMAGE_FSTYPES` contains "live"), 4244 :term:`INITRD_IMAGE` specifies the image recipe that should be built to 4245 provide the initial RAM disk image. The default value is 4246 "core-image-minimal-initramfs". 4247 4248 See the :ref:`ref-classes-image-live` class for more information. 4249 4250 :term:`INITSCRIPT_NAME` 4251 The filename of the initialization script as installed to 4252 ``${sysconfdir}/init.d``. 4253 4254 This variable is used in recipes when using :ref:`ref-classes-update-rc.d`. 4255 The variable is mandatory. 4256 4257 :term:`INITSCRIPT_PACKAGES` 4258 A list of the packages that contain initscripts. If multiple packages 4259 are specified, you need to append the package name to the other 4260 ``INITSCRIPT_*`` as an override. 4261 4262 This variable is used in recipes when using :ref:`ref-classes-update-rc.d`. 4263 The variable is optional and defaults to the :term:`PN` 4264 variable. 4265 4266 :term:`INITSCRIPT_PARAMS` 4267 Specifies the options to pass to ``update-rc.d``. Here is an example:: 4268 4269 INITSCRIPT_PARAMS = "start 99 5 2 . stop 20 0 1 6 ." 4270 4271 In this example, the script has a runlevel of 99, starts the script 4272 in initlevels 2 and 5, and stops the script in levels 0, 1 and 6. 4273 4274 The variable's default value is "defaults", which is set in the 4275 :ref:`ref-classes-update-rc.d` class. 4276 4277 The value in :term:`INITSCRIPT_PARAMS` is passed through to the 4278 ``update-rc.d`` command. For more information on valid parameters, 4279 please see the ``update-rc.d`` manual page at 4280 https://manpages.debian.org/buster/init-system-helpers/update-rc.d.8.en.html 4281 4282 :term:`INSANE_SKIP` 4283 Specifies the QA checks to skip for a specific package within a 4284 recipe. For example, to skip the check for symbolic link ``.so`` 4285 files in the main package of a recipe, add the following to the 4286 recipe. The package name override must be used, which in this example 4287 is ``${PN}``:: 4288 4289 INSANE_SKIP:${PN} += "dev-so" 4290 4291 See the ":ref:`ref-classes-insane`" section for a 4292 list of the valid QA checks you can specify using this variable. 4293 4294 :term:`INSTALL_TIMEZONE_FILE` 4295 By default, the ``tzdata`` recipe packages an ``/etc/timezone`` file. 4296 Set the :term:`INSTALL_TIMEZONE_FILE` variable to "0" at the 4297 configuration level to disable this behavior. 4298 4299 :term:`IPK_FEED_URIS` 4300 When the IPK backend is in use and package management is enabled on 4301 the target, you can use this variable to set up ``opkg`` in the 4302 target image to point to package feeds on a nominated server. Once 4303 the feed is established, you can perform installations or upgrades 4304 using the package manager at runtime. 4305 4306 :term:`KARCH` 4307 Defines the kernel architecture used when assembling the 4308 configuration. Architectures supported for this release are: 4309 4310 - powerpc 4311 - i386 4312 - x86_64 4313 - arm 4314 - qemu 4315 - mips 4316 4317 You define the :term:`KARCH` variable in the :ref:`kernel-dev/advanced:bsp descriptions`. 4318 4319 :term:`KBRANCH` 4320 A regular expression used by the build process to explicitly identify 4321 the kernel branch that is validated, patched, and configured during a 4322 build. You must set this variable to ensure the exact kernel branch 4323 you want is being used by the build process. 4324 4325 Values for this variable are set in the kernel's recipe file and the 4326 kernel's append file. For example, if you are using the 4327 ``linux-yocto_4.12`` kernel, the kernel recipe file is the 4328 ``meta/recipes-kernel/linux/linux-yocto_4.12.bb`` file. :term:`KBRANCH` 4329 is set as follows in that kernel recipe file:: 4330 4331 KBRANCH ?= "standard/base" 4332 4333 This variable is also used from the kernel's append file to identify 4334 the kernel branch specific to a particular machine or target 4335 hardware. Continuing with the previous kernel example, the kernel's 4336 append file (i.e. ``linux-yocto_4.12.bbappend``) is located in the 4337 BSP layer for a given machine. For example, the append file for the 4338 Beaglebone, EdgeRouter, and generic versions of both 32 and 64-bit IA 4339 machines (``meta-yocto-bsp``) is named 4340 ``meta-yocto-bsp/recipes-kernel/linux/linux-yocto_4.12.bbappend``. 4341 Here are the related statements from that append file:: 4342 4343 KBRANCH:genericx86 = "standard/base" 4344 KBRANCH:genericx86-64 = "standard/base" 4345 KBRANCH:edgerouter = "standard/edgerouter" 4346 KBRANCH:beaglebone = "standard/beaglebone" 4347 4348 The :term:`KBRANCH` statements 4349 identify the kernel branch to use when building for each supported 4350 BSP. 4351 4352 :term:`KBUILD_DEFCONFIG` 4353 When used with the :ref:`ref-classes-kernel-yocto` 4354 class, specifies an "in-tree" kernel configuration file for use 4355 during a kernel build. 4356 4357 Typically, when using a ``defconfig`` to configure a kernel during a 4358 build, you place the file in your layer in the same manner as you 4359 would place patch files and configuration fragment files (i.e. 4360 "out-of-tree"). However, if you want to use a ``defconfig`` file that 4361 is part of the kernel tree (i.e. "in-tree"), you can use the 4362 :term:`KBUILD_DEFCONFIG` variable and append the 4363 :term:`KMACHINE` variable to point to the 4364 ``defconfig`` file. 4365 4366 To use the variable, set it in the append file for your kernel recipe 4367 using the following form:: 4368 4369 KBUILD_DEFCONFIG:<machine> ?= "defconfig_file" 4370 4371 Here is an example from a "raspberrypi2" :term:`MACHINE` build that uses 4372 a ``defconfig`` file named "bcm2709_defconfig":: 4373 4374 KBUILD_DEFCONFIG:raspberrypi2 = "bcm2709_defconfig" 4375 4376 As an alternative, you can use the following within your append file:: 4377 4378 KBUILD_DEFCONFIG:pn-linux-yocto ?= "defconfig_file" 4379 4380 For more 4381 information on how to use the :term:`KBUILD_DEFCONFIG` variable, see the 4382 ":ref:`kernel-dev/common:using an "in-tree" \`\`defconfig\`\` file`" 4383 section in the Yocto Project Linux Kernel Development Manual. 4384 4385 :term:`KCONFIG_MODE` 4386 When used with the :ref:`ref-classes-kernel-yocto` 4387 class, specifies the kernel configuration values to use for options 4388 not specified in the provided ``defconfig`` file. Valid options are:: 4389 4390 KCONFIG_MODE = "alldefconfig" 4391 KCONFIG_MODE = "allnoconfig" 4392 4393 In ``alldefconfig`` mode the options not explicitly specified will be 4394 assigned their Kconfig default value. In ``allnoconfig`` mode the 4395 options not explicitly specified will be disabled in the kernel 4396 config. 4397 4398 In case :term:`KCONFIG_MODE` is not set the behaviour will depend on where 4399 the ``defconfig`` file is coming from. An "in-tree" ``defconfig`` file 4400 will be handled in ``alldefconfig`` mode, a ``defconfig`` file placed 4401 in ``${WORKDIR}`` through a meta-layer will be handled in 4402 ``allnoconfig`` mode. 4403 4404 An "in-tree" ``defconfig`` file can be selected via the 4405 :term:`KBUILD_DEFCONFIG` variable. :term:`KCONFIG_MODE` does not need to 4406 be explicitly set. 4407 4408 A ``defconfig`` file compatible with ``allnoconfig`` mode can be 4409 generated by copying the ``.config`` file from a working Linux kernel 4410 build, renaming it to ``defconfig`` and placing it into the Linux 4411 kernel ``${WORKDIR}`` through your meta-layer. :term:`KCONFIG_MODE` does 4412 not need to be explicitly set. 4413 4414 A ``defconfig`` file compatible with ``alldefconfig`` mode can be 4415 generated using the 4416 :ref:`ref-tasks-savedefconfig` 4417 task and placed into the Linux kernel ``${WORKDIR}`` through your 4418 meta-layer. Explicitely set :term:`KCONFIG_MODE`:: 4419 4420 KCONFIG_MODE = "alldefconfig" 4421 4422 :term:`KERNEL_ALT_IMAGETYPE` 4423 Specifies an alternate kernel image type for creation in addition to 4424 the kernel image type specified using the :term:`KERNEL_IMAGETYPE` and 4425 :term:`KERNEL_IMAGETYPES` variables. 4426 4427 :term:`KERNEL_ARTIFACT_NAME` 4428 Specifies the name of all of the build artifacts. You can change the 4429 name of the artifacts by changing the :term:`KERNEL_ARTIFACT_NAME` 4430 variable. 4431 4432 The value of :term:`KERNEL_ARTIFACT_NAME`, which is set in the 4433 ``meta/classes-recipe/kernel-artifact-names.bbclass`` file, has the 4434 following default value:: 4435 4436 KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}${IMAGE_MACHINE_SUFFIX}${IMAGE_VERSION_SUFFIX}" 4437 4438 See the :term:`PKGE`, :term:`PKGV`, :term:`PKGR`, :term:`IMAGE_MACHINE_SUFFIX` 4439 and :term:`IMAGE_VERSION_SUFFIX` variables for additional information. 4440 4441 :term:`KERNEL_CLASSES` 4442 A list of classes defining kernel image types that the 4443 :ref:`ref-classes-kernel` class should inherit. You typically 4444 append this variable to enable extended image types. An example is 4445 ":ref:`ref-classes-kernel-fitimage`", which enables 4446 FIT image support and resides in ``meta/classes-recipe/kernel-fitimage.bbclass``. 4447 You can register custom kernel image types with the 4448 :ref:`ref-classes-kernel` class using this variable. 4449 4450 :term:`KERNEL_DANGLING_FEATURES_WARN_ONLY` 4451 When kernel configuration fragments are missing for some 4452 :term:`KERNEL_FEATURES` specified by layers or BSPs, 4453 building and configuring the kernel stops with an error. 4454 4455 You can turn these errors into warnings by setting the 4456 following in ``conf/local.conf``:: 4457 4458 KERNEL_DANGLING_FEATURES_WARN_ONLY = "1" 4459 4460 You will still be warned that runtime issues may occur, 4461 but at least the kernel configuration and build process will 4462 be allowed to continue. 4463 4464 :term:`KERNEL_DEBUG_TIMESTAMPS` 4465 If set to "1", enables timestamping functionality during building 4466 the kernel. The default is "0" to disable this for reproducibility 4467 reasons. 4468 4469 :term:`KERNEL_DEPLOY_DEPEND` 4470 Provides a means of controlling the dependency of an image recipe 4471 on the kernel. The default value is "virtual/kernel:do_deploy", 4472 however for a small initramfs image or other images that do not 4473 need the kernel, this can be set to "" in the image recipe. 4474 4475 :term:`KERNEL_DEVICETREE` 4476 Specifies the name of the generated Linux kernel device tree (i.e. 4477 the ``.dtb``) file. 4478 4479 .. note:: 4480 4481 There is legacy support for specifying the full path to the device 4482 tree. However, providing just the ``.dtb`` file is preferred. 4483 4484 In order to use this variable, the :ref:`ref-classes-kernel-devicetree` 4485 class must be inherited. 4486 4487 :term:`KERNEL_DEVICETREE_BUNDLE` 4488 When set to "1", this variable allows to bundle the Linux kernel 4489 and the Device Tree Binary together in a single file. 4490 4491 This feature is currently only supported on the "arm" (32 bit) 4492 architecture. 4493 4494 This variable is set to "0" by default by the 4495 :ref:`ref-classes-kernel-devicetree` class. 4496 4497 :term:`KERNEL_DTB_LINK_NAME` 4498 The link name of the kernel device tree binary (DTB). This variable 4499 is set in the ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as 4500 follows:: 4501 4502 KERNEL_DTB_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}" 4503 4504 The 4505 value of the ``KERNEL_ARTIFACT_LINK_NAME`` variable, which is set in 4506 the same file, has the following value:: 4507 4508 KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}" 4509 4510 See the :term:`MACHINE` variable for additional 4511 information. 4512 4513 :term:`KERNEL_DTB_NAME` 4514 The base name of the kernel device tree binary (DTB). This variable 4515 is set in the ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as 4516 follows:: 4517 4518 KERNEL_DTB_NAME ?= "${KERNEL_ARTIFACT_NAME}" 4519 4520 See :term:`KERNEL_ARTIFACT_NAME` for additional information. 4521 4522 :term:`KERNEL_DTBDEST` 4523 This variable, used by the :ref:`ref-classes-kernel-devicetree` 4524 class, allows to change the installation directory of the DTB 4525 (Device Tree Binary) files. 4526 4527 It is set by default to "${KERNEL_IMAGEDEST}" by the 4528 :ref:`ref-classes-kernel` class. 4529 4530 :term:`KERNEL_DTBVENDORED` 4531 This variable, used by the :ref:`ref-classes-kernel-devicetree`, 4532 allows to ignore vendor subdirectories when installing DTB 4533 (Device Tree Binary) files, when it is set to "false". 4534 4535 To keep vendor subdirectories, set this variable to "true". 4536 4537 It is set by default to "false" by the :ref:`ref-classes-kernel` class. 4538 4539 :term:`KERNEL_DTC_FLAGS` 4540 Specifies the ``dtc`` flags that are passed to the Linux kernel build 4541 system when generating the device trees (via ``DTC_FLAGS`` environment 4542 variable). 4543 4544 In order to use this variable, the :ref:`ref-classes-kernel-devicetree` 4545 class must be inherited. 4546 4547 :term:`KERNEL_EXTRA_ARGS` 4548 Specifies additional ``make`` command-line arguments the OpenEmbedded 4549 build system passes on when compiling the kernel. 4550 4551 :term:`KERNEL_FEATURES` 4552 Includes additional kernel metadata. In the OpenEmbedded build 4553 system, the default Board Support Packages (BSPs) 4554 :term:`Metadata` is provided through the 4555 :term:`KMACHINE` and :term:`KBRANCH` 4556 variables. You can use the :term:`KERNEL_FEATURES` variable from within 4557 the kernel recipe or kernel append file to further add metadata for 4558 all BSPs or specific BSPs. 4559 4560 The metadata you add through this variable includes config fragments 4561 and features descriptions, which usually includes patches as well as 4562 config fragments. You typically override the :term:`KERNEL_FEATURES` 4563 variable for a specific machine. In this way, you can provide 4564 validated, but optional, sets of kernel configurations and features. 4565 4566 For example, the following example from the ``linux-yocto-rt_4.12`` 4567 kernel recipe adds "netfilter" and "taskstats" features to all BSPs 4568 as well as "virtio" configurations to all QEMU machines. The last two 4569 statements add specific configurations to targeted machine types:: 4570 4571 KERNEL_EXTRA_FEATURES ?= "features/netfilter/netfilter.scc features/taskstats/taskstats.scc" 4572 KERNEL_FEATURES:append = " ${KERNEL_EXTRA_FEATURES}" 4573 KERNEL_FEATURES:append:qemuall = " cfg/virtio.scc" 4574 KERNEL_FEATURES:append:qemux86 = " cfg/sound.scc cfg/paravirt_kvm.scc" 4575 KERNEL_FEATURES:append:qemux86-64 = " cfg/sound.scc" 4576 4577 :term:`KERNEL_FIT_LINK_NAME` 4578 The link name of the kernel flattened image tree (FIT) image. This 4579 variable is set in the ``meta/classes-recipe/kernel-artifact-names.bbclass`` 4580 file as follows:: 4581 4582 KERNEL_FIT_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}" 4583 4584 The value of the 4585 ``KERNEL_ARTIFACT_LINK_NAME`` variable, which is set in the same 4586 file, has the following value:: 4587 4588 KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}" 4589 4590 See the :term:`MACHINE` variable for additional 4591 information. 4592 4593 :term:`KERNEL_FIT_NAME` 4594 The base name of the kernel flattened image tree (FIT) image. This 4595 variable is set in the ``meta/classes-recipe/kernel-artifact-names.bbclass`` 4596 file as follows:: 4597 4598 KERNEL_FIT_NAME ?= "${KERNEL_ARTIFACT_NAME}" 4599 4600 See :term:`KERNEL_ARTIFACT_NAME` for additional information. 4601 4602 :term:`KERNEL_IMAGE_LINK_NAME` 4603 The link name for the kernel image. This variable is set in the 4604 ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as follows:: 4605 4606 KERNEL_IMAGE_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}" 4607 4608 The value of 4609 the ``KERNEL_ARTIFACT_LINK_NAME`` variable, which is set in the same 4610 file, has the following value:: 4611 4612 KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}" 4613 4614 See the :term:`MACHINE` variable for additional 4615 information. 4616 4617 :term:`KERNEL_IMAGE_MAXSIZE` 4618 Specifies the maximum size of the kernel image file in kilobytes. If 4619 :term:`KERNEL_IMAGE_MAXSIZE` is set, the size of the kernel image file is 4620 checked against the set value during the 4621 :ref:`ref-tasks-sizecheck` task. The task fails if 4622 the kernel image file is larger than the setting. 4623 4624 :term:`KERNEL_IMAGE_MAXSIZE` is useful for target devices that have a 4625 limited amount of space in which the kernel image must be stored. 4626 4627 By default, this variable is not set, which means the size of the 4628 kernel image is not checked. 4629 4630 :term:`KERNEL_IMAGE_NAME` 4631 The base name of the kernel image. This variable is set in the 4632 ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as follows:: 4633 4634 KERNEL_IMAGE_NAME ?= "${KERNEL_ARTIFACT_NAME}" 4635 4636 See :term:`KERNEL_ARTIFACT_NAME` for additional information. 4637 4638 :term:`KERNEL_IMAGETYPE` 4639 The type of kernel to build for a device, usually set by the machine 4640 configuration files and defaults to "zImage". This variable is used 4641 when building the kernel and is passed to ``make`` as the target to 4642 build. 4643 4644 To build additional kernel image types, use :term:`KERNEL_IMAGETYPES`. 4645 4646 :term:`KERNEL_IMAGETYPES` 4647 Lists additional types of kernel images to build for a device in addition 4648 to image type specified in :term:`KERNEL_IMAGETYPE`. Usually set by the 4649 machine configuration files. 4650 4651 :term:`KERNEL_MODULE_AUTOLOAD` 4652 Lists kernel modules that need to be auto-loaded during boot. 4653 4654 .. note:: 4655 4656 This variable replaces the deprecated :term:`module_autoload` 4657 variable. 4658 4659 You can use the :term:`KERNEL_MODULE_AUTOLOAD` variable anywhere that it 4660 can be recognized by the kernel recipe or by an out-of-tree kernel 4661 module recipe (e.g. a machine configuration file, a distribution 4662 configuration file, an append file for the recipe, or the recipe 4663 itself). 4664 4665 Specify it as follows:: 4666 4667 KERNEL_MODULE_AUTOLOAD += "module_name1 module_name2 module_name3" 4668 4669 Including :term:`KERNEL_MODULE_AUTOLOAD` causes the OpenEmbedded build 4670 system to populate the ``/etc/modules-load.d/modname.conf`` file with 4671 the list of modules to be auto-loaded on boot. The modules appear 4672 one-per-line in the file. Here is an example of the most common use 4673 case:: 4674 4675 KERNEL_MODULE_AUTOLOAD += "module_name" 4676 4677 For information on how to populate the ``modname.conf`` file with 4678 ``modprobe.d`` syntax lines, see the :term:`KERNEL_MODULE_PROBECONF` variable. 4679 4680 :term:`KERNEL_MODULE_PROBECONF` 4681 Provides a list of modules for which the OpenEmbedded build system 4682 expects to find ``module_conf_``\ modname values that specify 4683 configuration for each of the modules. For information on how to 4684 provide those module configurations, see the 4685 :term:`module_conf_* <module_conf>` variable. 4686 4687 :term:`KERNEL_PACKAGE_NAME` 4688 Specifies the base name of the kernel packages, such as "kernel" 4689 in the kernel packages such as "kernel-modules", "kernel-image" and 4690 "kernel-dbg". 4691 4692 The default value for this variable is set to "kernel" by the 4693 :ref:`ref-classes-kernel` class. 4694 4695 :term:`KERNEL_PATH` 4696 The location of the kernel sources. This variable is set to the value 4697 of the :term:`STAGING_KERNEL_DIR` within the :ref:`ref-classes-module` 4698 class. For information on how this variable is used, see the 4699 ":ref:`kernel-dev/common:incorporating out-of-tree modules`" 4700 section in the Yocto Project Linux Kernel Development Manual. 4701 4702 To help maximize compatibility with out-of-tree drivers used to build 4703 modules, the OpenEmbedded build system also recognizes and uses the 4704 :term:`KERNEL_SRC` variable, which is identical to 4705 the :term:`KERNEL_PATH` variable. Both variables are common variables 4706 used by external Makefiles to point to the kernel source directory. 4707 4708 :term:`KERNEL_SRC` 4709 The location of the kernel sources. This variable is set to the value 4710 of the :term:`STAGING_KERNEL_DIR` within the :ref:`ref-classes-module` 4711 class. For information on how this variable is used, see the 4712 ":ref:`kernel-dev/common:incorporating out-of-tree modules`" 4713 section in the Yocto Project Linux Kernel Development Manual. 4714 4715 To help maximize compatibility with out-of-tree drivers used to build 4716 modules, the OpenEmbedded build system also recognizes and uses the 4717 :term:`KERNEL_PATH` variable, which is identical 4718 to the :term:`KERNEL_SRC` variable. Both variables are common variables 4719 used by external Makefiles to point to the kernel source directory. 4720 4721 :term:`KERNEL_VERSION` 4722 Specifies the version of the kernel as extracted from ``version.h`` 4723 or ``utsrelease.h`` within the kernel sources. Effects of setting 4724 this variable do not take effect until the kernel has been 4725 configured. Consequently, attempting to refer to this variable in 4726 contexts prior to configuration will not work. 4727 4728 :term:`KERNELDEPMODDEPEND` 4729 Specifies whether the data referenced through 4730 :term:`PKGDATA_DIR` is needed or not. 4731 :term:`KERNELDEPMODDEPEND` does not control whether or not that data 4732 exists, but simply whether or not it is used. If you do not need to 4733 use the data, set the :term:`KERNELDEPMODDEPEND` variable in your 4734 :term:`Initramfs` recipe. Setting the variable there when the data is not 4735 needed avoids a potential dependency loop. 4736 4737 :term:`KFEATURE_DESCRIPTION` 4738 Provides a short description of a configuration fragment. You use 4739 this variable in the ``.scc`` file that describes a configuration 4740 fragment file. Here is the variable used in a file named ``smp.scc`` 4741 to describe SMP being enabled:: 4742 4743 define KFEATURE_DESCRIPTION "Enable SMP" 4744 4745 :term:`KMACHINE` 4746 The machine as known by the kernel. Sometimes the machine name used 4747 by the kernel does not match the machine name used by the 4748 OpenEmbedded build system. For example, the machine name that the 4749 OpenEmbedded build system understands as ``core2-32-intel-common`` 4750 goes by a different name in the Linux Yocto kernel. The kernel 4751 understands that machine as ``intel-core2-32``. For cases like these, 4752 the :term:`KMACHINE` variable maps the kernel machine name to the 4753 OpenEmbedded build system machine name. 4754 4755 These mappings between different names occur in the Yocto Linux 4756 Kernel's ``meta`` branch. As an example take a look in the 4757 ``common/recipes-kernel/linux/linux-yocto_3.19.bbappend`` file:: 4758 4759 LINUX_VERSION:core2-32-intel-common = "3.19.0" 4760 COMPATIBLE_MACHINE:core2-32-intel-common = "${MACHINE}" 4761 SRCREV_meta:core2-32-intel-common = "8897ef68b30e7426bc1d39895e71fb155d694974" 4762 SRCREV_machine:core2-32-intel-common = "43b9eced9ba8a57add36af07736344dcc383f711" 4763 KMACHINE:core2-32-intel-common = "intel-core2-32" 4764 KBRANCH:core2-32-intel-common = "standard/base" 4765 KERNEL_FEATURES:append:core2-32-intel-common = " ${KERNEL_FEATURES_INTEL_COMMON}" 4766 4767 The :term:`KMACHINE` statement says 4768 that the kernel understands the machine name as "intel-core2-32". 4769 However, the OpenEmbedded build system understands the machine as 4770 "core2-32-intel-common". 4771 4772 :term:`KTYPE` 4773 Defines the kernel type to be used in assembling the configuration. 4774 The linux-yocto recipes define "standard", "tiny", and "preempt-rt" 4775 kernel types. See the ":ref:`kernel-dev/advanced:kernel types`" 4776 section in the 4777 Yocto Project Linux Kernel Development Manual for more information on 4778 kernel types. 4779 4780 You define the :term:`KTYPE` variable in the 4781 :ref:`kernel-dev/advanced:bsp descriptions`. The 4782 value you use must match the value used for the 4783 :term:`LINUX_KERNEL_TYPE` value used by the 4784 kernel recipe. 4785 4786 :term:`LABELS` 4787 Provides a list of targets for automatic configuration. 4788 4789 See the :ref:`ref-classes-grub-efi` class for more 4790 information on how this variable is used. 4791 4792 :term:`LAYERDEPENDS` 4793 Lists the layers, separated by spaces, on which this recipe depends. 4794 Optionally, you can specify a specific layer version for a dependency 4795 by adding it to the end of the layer name. Here is an example:: 4796 4797 LAYERDEPENDS_mylayer = "anotherlayer (=3)" 4798 4799 In this previous example, 4800 version 3 of "anotherlayer" is compared against 4801 :term:`LAYERVERSION`\ ``_anotherlayer``. 4802 4803 An error is produced if any dependency is missing or the version 4804 numbers (if specified) do not match exactly. This variable is used in 4805 the ``conf/layer.conf`` file and must be suffixed with the name of 4806 the specific layer (e.g. ``LAYERDEPENDS_mylayer``). 4807 4808 :term:`LAYERDIR` 4809 When used inside the ``layer.conf`` configuration file, this variable 4810 provides the path of the current layer. This variable is not 4811 available outside of ``layer.conf`` and references are expanded 4812 immediately when parsing of the file completes. 4813 4814 :term:`LAYERDIR_RE` 4815 See :term:`bitbake:LAYERDIR_RE` in the BitBake manual. 4816 4817 :term:`LAYERRECOMMENDS` 4818 Lists the layers, separated by spaces, recommended for use with this 4819 layer. 4820 4821 Optionally, you can specify a specific layer version for a 4822 recommendation by adding the version to the end of the layer name. 4823 Here is an example:: 4824 4825 LAYERRECOMMENDS_mylayer = "anotherlayer (=3)" 4826 4827 In this previous example, version 3 of "anotherlayer" is compared 4828 against ``LAYERVERSION_anotherlayer``. 4829 4830 This variable is used in the ``conf/layer.conf`` file and must be 4831 suffixed with the name of the specific layer (e.g. 4832 ``LAYERRECOMMENDS_mylayer``). 4833 4834 :term:`LAYERSERIES_COMPAT` 4835 See :term:`bitbake:LAYERSERIES_COMPAT` in the BitBake manual. 4836 4837 :term:`LAYERVERSION` 4838 Optionally specifies the version of a layer as a single number. You 4839 can use this within :term:`LAYERDEPENDS` for 4840 another layer in order to depend on a specific version of the layer. 4841 This variable is used in the ``conf/layer.conf`` file and must be 4842 suffixed with the name of the specific layer (e.g. 4843 ``LAYERVERSION_mylayer``). 4844 4845 :term:`LD` 4846 The minimal command and arguments used to run the linker. 4847 4848 :term:`LDFLAGS` 4849 Specifies the flags to pass to the linker. This variable is exported 4850 to an environment variable and thus made visible to the software 4851 being built during the compilation step. 4852 4853 Default initialization for :term:`LDFLAGS` varies depending on what is 4854 being built: 4855 4856 - :term:`TARGET_LDFLAGS` when building for the 4857 target 4858 4859 - :term:`BUILD_LDFLAGS` when building for the 4860 build host (i.e. ``-native``) 4861 4862 - :term:`BUILDSDK_LDFLAGS` when building for 4863 an SDK (i.e. ``nativesdk-``) 4864 4865 :term:`LEAD_SONAME` 4866 Specifies the lead (or primary) compiled library file (i.e. ``.so``) 4867 that the :ref:`ref-classes-debian` class applies its 4868 naming policy to given a recipe that packages multiple libraries. 4869 4870 This variable works in conjunction with the :ref:`ref-classes-debian` 4871 class. 4872 4873 :term:`LIC_FILES_CHKSUM` 4874 Checksums of the license text in the recipe source code. 4875 4876 This variable tracks changes in license text of the source code 4877 files. If the license text is changed, it will trigger a build 4878 failure, which gives the developer an opportunity to review any 4879 license change. 4880 4881 This variable must be defined for all recipes (unless 4882 :term:`LICENSE` is set to "CLOSED"). 4883 4884 For more information, see the ":ref:`dev-manual/licenses:tracking license changes`" 4885 section in the Yocto Project Development Tasks Manual. 4886 4887 :term:`LICENSE` 4888 The list of source licenses for the recipe. Follow these rules: 4889 4890 - Do not use spaces within individual license names. 4891 4892 - Separate license names using \| (pipe) when there is a choice 4893 between licenses. 4894 4895 - Separate license names using & (ampersand) when there are 4896 multiple licenses for different parts of the source. 4897 4898 - You can use spaces between license names. 4899 4900 - For standard licenses, use the names of the files in 4901 ``meta/files/common-licenses/`` or the 4902 :term:`SPDXLICENSEMAP` flag names defined in 4903 ``meta/conf/licenses.conf``. 4904 4905 Here are some examples:: 4906 4907 LICENSE = "LGPL-2.1-only | GPL-3.0-only" 4908 LICENSE = "MPL-1.0 & LGPL-2.1-only" 4909 LICENSE = "GPL-2.0-or-later" 4910 4911 The first example is from the 4912 recipes for Qt, which the user may choose to distribute under either 4913 the LGPL version 2.1 or GPL version 3. The second example is from 4914 Cairo where two licenses cover different parts of the source code. 4915 The final example is from ``sysstat``, which presents a single 4916 license. 4917 4918 You can also specify licenses on a per-package basis to handle 4919 situations where components of the output have different licenses. 4920 For example, a piece of software whose code is licensed under GPLv2 4921 but has accompanying documentation licensed under the GNU Free 4922 Documentation License 1.2 could be specified as follows:: 4923 4924 LICENSE = "GFDL-1.2 & GPL-2.0-only" 4925 LICENSE:${PN} = "GPL-2.0.only" 4926 LICENSE:${PN}-doc = "GFDL-1.2" 4927 4928 :term:`LICENSE_CREATE_PACKAGE` 4929 Setting :term:`LICENSE_CREATE_PACKAGE` to "1" causes the OpenEmbedded 4930 build system to create an extra package (i.e. 4931 ``${``\ :term:`PN`\ ``}-lic``) for each recipe and to add 4932 those packages to the 4933 :term:`RRECOMMENDS`\ ``:${PN}``. 4934 4935 The ``${PN}-lic`` package installs a directory in 4936 ``/usr/share/licenses`` named ``${PN}``, which is the recipe's base 4937 name, and installs files in that directory that contain license and 4938 copyright information (i.e. copies of the appropriate license files 4939 from ``meta/common-licenses`` that match the licenses specified in 4940 the :term:`LICENSE` variable of the recipe metadata 4941 and copies of files marked in 4942 :term:`LIC_FILES_CHKSUM` as containing 4943 license text). 4944 4945 For related information on providing license text, see the 4946 :term:`COPY_LIC_DIRS` variable, the 4947 :term:`COPY_LIC_MANIFEST` variable, and the 4948 ":ref:`dev-manual/licenses:providing license text`" 4949 section in the Yocto Project Development Tasks Manual. 4950 4951 :term:`LICENSE_FLAGS` 4952 Specifies additional flags for a recipe you must allow through 4953 :term:`LICENSE_FLAGS_ACCEPTED` in 4954 order for the recipe to be built. When providing multiple flags, 4955 separate them with spaces. 4956 4957 This value is independent of :term:`LICENSE` and is 4958 typically used to mark recipes that might require additional licenses 4959 in order to be used in a commercial product. For more information, 4960 see the 4961 ":ref:`dev-manual/licenses:enabling commercially licensed recipes`" 4962 section in the Yocto Project Development Tasks Manual. 4963 4964 :term:`LICENSE_FLAGS_ACCEPTED` 4965 Lists license flags that when specified in 4966 :term:`LICENSE_FLAGS` within a recipe should not 4967 prevent that recipe from being built. For more information, see the 4968 ":ref:`dev-manual/licenses:enabling commercially licensed recipes`" 4969 section in the Yocto Project Development Tasks Manual. 4970 4971 :term:`LICENSE_PATH` 4972 Path to additional licenses used during the build. By default, the 4973 OpenEmbedded build system uses :term:`COMMON_LICENSE_DIR` to define the 4974 directory that holds common license text used during the build. The 4975 :term:`LICENSE_PATH` variable allows you to extend that location to other 4976 areas that have additional licenses:: 4977 4978 LICENSE_PATH += "path-to-additional-common-licenses" 4979 4980 :term:`LINUX_KERNEL_TYPE` 4981 Defines the kernel type to be used in assembling the configuration. 4982 The linux-yocto recipes define "standard", "tiny", and "preempt-rt" 4983 kernel types. See the ":ref:`kernel-dev/advanced:kernel types`" 4984 section in the 4985 Yocto Project Linux Kernel Development Manual for more information on 4986 kernel types. 4987 4988 If you do not specify a :term:`LINUX_KERNEL_TYPE`, it defaults to 4989 "standard". Together with :term:`KMACHINE`, the 4990 :term:`LINUX_KERNEL_TYPE` variable defines the search arguments used by 4991 the kernel tools to find the appropriate description within the 4992 kernel :term:`Metadata` with which to build out the sources 4993 and configuration. 4994 4995 :term:`LINUX_VERSION` 4996 The Linux version from ``kernel.org`` on which the Linux kernel image 4997 being built using the OpenEmbedded build system is based. You define 4998 this variable in the kernel recipe. For example, the 4999 ``linux-yocto-3.4.bb`` kernel recipe found in 5000 ``meta/recipes-kernel/linux`` defines the variables as follows:: 5001 5002 LINUX_VERSION ?= "3.4.24" 5003 5004 The :term:`LINUX_VERSION` variable is used to define :term:`PV` 5005 for the recipe:: 5006 5007 PV = "${LINUX_VERSION}+git${SRCPV}" 5008 5009 :term:`LINUX_VERSION_EXTENSION` 5010 A string extension compiled into the version string of the Linux 5011 kernel built with the OpenEmbedded build system. You define this 5012 variable in the kernel recipe. For example, the linux-yocto kernel 5013 recipes all define the variable as follows:: 5014 5015 LINUX_VERSION_EXTENSION ?= "-yocto-${LINUX_KERNEL_TYPE}" 5016 5017 Defining this variable essentially sets the Linux kernel 5018 configuration item ``CONFIG_LOCALVERSION``, which is visible through 5019 the ``uname`` command. Here is an example that shows the extension 5020 assuming it was set as previously shown:: 5021 5022 $ uname -r 5023 3.7.0-rc8-custom 5024 5025 :term:`LOG_DIR` 5026 Specifies the directory to which the OpenEmbedded build system writes 5027 overall log files. The default directory is ``${TMPDIR}/log``. 5028 5029 For the directory containing logs specific to each task, see the 5030 :term:`T` variable. 5031 5032 :term:`MACHINE` 5033 Specifies the target device for which the image is built. You define 5034 :term:`MACHINE` in the ``local.conf`` file found in the 5035 :term:`Build Directory`. By default, :term:`MACHINE` is set to 5036 "qemux86", which is an x86-based architecture machine to be emulated 5037 using QEMU:: 5038 5039 MACHINE ?= "qemux86" 5040 5041 The variable corresponds to a machine configuration file of the same 5042 name, through which machine-specific configurations are set. Thus, 5043 when :term:`MACHINE` is set to "qemux86", the corresponding 5044 ``qemux86.conf`` machine configuration file can be found in 5045 the :term:`Source Directory` in 5046 ``meta/conf/machine``. 5047 5048 The list of machines supported by the Yocto Project as shipped 5049 include the following:: 5050 5051 MACHINE ?= "qemuarm" 5052 MACHINE ?= "qemuarm64" 5053 MACHINE ?= "qemumips" 5054 MACHINE ?= "qemumips64" 5055 MACHINE ?= "qemuppc" 5056 MACHINE ?= "qemux86" 5057 MACHINE ?= "qemux86-64" 5058 MACHINE ?= "genericx86" 5059 MACHINE ?= "genericx86-64" 5060 MACHINE ?= "beaglebone" 5061 MACHINE ?= "edgerouter" 5062 5063 The last five are Yocto Project reference hardware 5064 boards, which are provided in the ``meta-yocto-bsp`` layer. 5065 5066 .. note:: 5067 5068 Adding additional Board Support Package (BSP) layers to your 5069 configuration adds new possible settings for :term:`MACHINE`. 5070 5071 :term:`MACHINE_ARCH` 5072 Specifies the name of the machine-specific architecture. This 5073 variable is set automatically from :term:`MACHINE` or 5074 :term:`TUNE_PKGARCH`. You should not hand-edit 5075 the :term:`MACHINE_ARCH` variable. 5076 5077 :term:`MACHINE_ESSENTIAL_EXTRA_RDEPENDS` 5078 A list of required machine-specific packages to install as part of 5079 the image being built. The build process depends on these packages 5080 being present. Furthermore, because this is a "machine-essential" 5081 variable, the list of packages are essential for the machine to boot. 5082 The impact of this variable affects images based on 5083 ``packagegroup-core-boot``, including the ``core-image-minimal`` 5084 image. 5085 5086 This variable is similar to the 5087 :term:`MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS` variable with the exception 5088 that the image being built has a build dependency on the variable's 5089 list of packages. In other words, the image will not build if a file 5090 in this list is not found. 5091 5092 As an example, suppose the machine for which you are building 5093 requires ``example-init`` to be run during boot to initialize the 5094 hardware. In this case, you would use the following in the machine's 5095 ``.conf`` configuration file:: 5096 5097 MACHINE_ESSENTIAL_EXTRA_RDEPENDS += "example-init" 5098 5099 :term:`MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS` 5100 A list of recommended machine-specific packages to install as part of 5101 the image being built. The build process does not depend on these 5102 packages being present. However, because this is a 5103 "machine-essential" variable, the list of packages are essential for 5104 the machine to boot. The impact of this variable affects images based 5105 on ``packagegroup-core-boot``, including the ``core-image-minimal`` 5106 image. 5107 5108 This variable is similar to the :term:`MACHINE_ESSENTIAL_EXTRA_RDEPENDS` 5109 variable with the exception that the image being built does not have 5110 a build dependency on the variable's list of packages. In other 5111 words, the image will still build if a package in this list is not 5112 found. Typically, this variable is used to handle essential kernel 5113 modules, whose functionality may be selected to be built into the 5114 kernel rather than as a module, in which case a package will not be 5115 produced. 5116 5117 Consider an example where you have a custom kernel where a specific 5118 touchscreen driver is required for the machine to be usable. However, 5119 the driver can be built as a module or into the kernel depending on 5120 the kernel configuration. If the driver is built as a module, you 5121 want it to be installed. But, when the driver is built into the 5122 kernel, you still want the build to succeed. This variable sets up a 5123 "recommends" relationship so that in the latter case, the build will 5124 not fail due to the missing package. To accomplish this, assuming the 5125 package for the module was called ``kernel-module-ab123``, you would 5126 use the following in the machine's ``.conf`` configuration file:: 5127 5128 MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS += "kernel-module-ab123" 5129 5130 .. note:: 5131 5132 In this example, the ``kernel-module-ab123`` recipe needs to 5133 explicitly set its :term:`PACKAGES` variable to ensure that BitBake 5134 does not use the kernel recipe's :term:`PACKAGES_DYNAMIC` variable to 5135 satisfy the dependency. 5136 5137 Some examples of these machine essentials are flash, screen, 5138 keyboard, mouse, or touchscreen drivers (depending on the machine). 5139 5140 :term:`MACHINE_EXTRA_RDEPENDS` 5141 A list of machine-specific packages to install as part of the image 5142 being built that are not essential for the machine to boot. However, 5143 the build process for more fully-featured images depends on the 5144 packages being present. 5145 5146 This variable affects all images based on ``packagegroup-base``, 5147 which does not include the ``core-image-minimal`` or 5148 ``core-image-full-cmdline`` images. 5149 5150 The variable is similar to the :term:`MACHINE_EXTRA_RRECOMMENDS` variable 5151 with the exception that the image being built has a build dependency 5152 on the variable's list of packages. In other words, the image will 5153 not build if a file in this list is not found. 5154 5155 An example is a machine that has WiFi capability but is not essential 5156 for the machine to boot the image. However, if you are building a 5157 more fully-featured image, you want to enable the WiFi. The package 5158 containing the firmware for the WiFi hardware is always expected to 5159 exist, so it is acceptable for the build process to depend upon 5160 finding the package. In this case, assuming the package for the 5161 firmware was called ``wifidriver-firmware``, you would use the 5162 following in the ``.conf`` file for the machine:: 5163 5164 MACHINE_EXTRA_RDEPENDS += "wifidriver-firmware" 5165 5166 :term:`MACHINE_EXTRA_RRECOMMENDS` 5167 A list of machine-specific packages to install as part of the image 5168 being built that are not essential for booting the machine. The image 5169 being built has no build dependency on this list of packages. 5170 5171 This variable affects only images based on ``packagegroup-base``, 5172 which does not include the ``core-image-minimal`` or 5173 ``core-image-full-cmdline`` images. 5174 5175 This variable is similar to the :term:`MACHINE_EXTRA_RDEPENDS` variable 5176 with the exception that the image being built does not have a build 5177 dependency on the variable's list of packages. In other words, the 5178 image will build if a file in this list is not found. 5179 5180 An example is a machine that has WiFi capability but is not essential 5181 For the machine to boot the image. However, if you are building a 5182 more fully-featured image, you want to enable WiFi. In this case, the 5183 package containing the WiFi kernel module will not be produced if the 5184 WiFi driver is built into the kernel, in which case you still want 5185 the build to succeed instead of failing as a result of the package 5186 not being found. To accomplish this, assuming the package for the 5187 module was called ``kernel-module-examplewifi``, you would use the 5188 following in the ``.conf`` file for the machine:: 5189 5190 MACHINE_EXTRA_RRECOMMENDS += "kernel-module-examplewifi" 5191 5192 :term:`MACHINE_FEATURES` 5193 Specifies the list of hardware features the 5194 :term:`MACHINE` is capable of supporting. For related 5195 information on enabling features, see the 5196 :term:`DISTRO_FEATURES`, 5197 :term:`COMBINED_FEATURES`, and 5198 :term:`IMAGE_FEATURES` variables. 5199 5200 For a list of hardware features supported by the Yocto Project as 5201 shipped, see the ":ref:`ref-features-machine`" section. 5202 5203 :term:`MACHINE_FEATURES_BACKFILL` 5204 A list of space-separated features to be added to 5205 :term:`MACHINE_FEATURES` if not also present in 5206 :term:`MACHINE_FEATURES_BACKFILL_CONSIDERED`. 5207 5208 This variable is set in the ``meta/conf/bitbake.conf`` file. It is not 5209 intended to be user-configurable. It is best to just reference the 5210 variable to see which machine features are being 5211 :ref:`backfilled <ref-features-backfill>` for all machine configurations. 5212 5213 :term:`MACHINE_FEATURES_BACKFILL_CONSIDERED` 5214 A list of space-separated features from :term:`MACHINE_FEATURES_BACKFILL` 5215 that should not be :ref:`backfilled <ref-features-backfill>` (i.e. added 5216 to :term:`MACHINE_FEATURES`) during the build. 5217 5218 This corresponds to an opt-out mechanism. When new default machine 5219 features are introduced, machine definition maintainers can review 5220 (`consider`) them and decide to exclude them from the 5221 :ref:`backfilled <ref-features-backfill>` features. Therefore, the 5222 combination of :term:`MACHINE_FEATURES_BACKFILL` and 5223 :term:`MACHINE_FEATURES_BACKFILL_CONSIDERED` makes it possible to 5224 add new default features without breaking existing machine definitions. 5225 5226 :term:`MACHINEOVERRIDES` 5227 A colon-separated list of overrides that apply to the current 5228 machine. By default, this list includes the value of 5229 :term:`MACHINE`. 5230 5231 You can extend :term:`MACHINEOVERRIDES` to add extra overrides that 5232 should apply to a machine. For example, all machines emulated in QEMU 5233 (e.g. ``qemuarm``, ``qemux86``, and so forth) include a file named 5234 ``meta/conf/machine/include/qemu.inc`` that prepends the following 5235 override to :term:`MACHINEOVERRIDES`:: 5236 5237 MACHINEOVERRIDES =. "qemuall:" 5238 5239 This 5240 override allows variables to be overridden for all machines emulated 5241 in QEMU, like in the following example from the ``connman-conf`` 5242 recipe:: 5243 5244 SRC_URI:append:qemuall = " file://wired.config \ 5245 file://wired-setup \ 5246 " 5247 5248 The underlying mechanism behind 5249 :term:`MACHINEOVERRIDES` is simply that it is included in the default 5250 value of :term:`OVERRIDES`. 5251 5252 :term:`MAINTAINER` 5253 The email address of the distribution maintainer. 5254 5255 :term:`MESON_BUILDTYPE` 5256 Value of the Meson ``--buildtype`` argument used by the 5257 :ref:`ref-classes-meson` class. It defaults to ``debug`` if 5258 :term:`DEBUG_BUILD` is set to "1", and ``plain`` otherwise. 5259 5260 See `Meson build options <https://mesonbuild.com/Builtin-options.html>`__ 5261 for the values you could set in a recipe. Values such as ``plain``, 5262 ``debug``, ``debugoptimized``, ``release`` and ``minsize`` allow 5263 you to specify the inclusion of debugging symbols and the compiler 5264 optimizations (none, performance or size). 5265 5266 :term:`METADATA_BRANCH` 5267 The branch currently checked out for the OpenEmbedded-Core layer (path 5268 determined by :term:`COREBASE`). 5269 5270 :term:`METADATA_REVISION` 5271 The revision currently checked out for the OpenEmbedded-Core layer (path 5272 determined by :term:`COREBASE`). 5273 5274 :term:`MIME_XDG_PACKAGES` 5275 The current implementation of the :ref:`ref-classes-mime-xdg` 5276 class cannot detect ``.desktop`` files installed through absolute 5277 symbolic links. Use this setting to make the class create post-install 5278 and post-remove scripts for these packages anyway, to invoke the 5279 ``update-destop-database`` command. 5280 5281 :term:`MIRRORS` 5282 Specifies additional paths from which the OpenEmbedded build system 5283 gets source code. When the build system searches for source code, it 5284 first tries the local download directory. If that location fails, the 5285 build system tries locations defined by 5286 :term:`PREMIRRORS`, the upstream source, and then 5287 locations specified by :term:`MIRRORS` in that order. 5288 5289 Assuming your distribution (:term:`DISTRO`) is "poky", 5290 the default value for :term:`MIRRORS` is defined in the 5291 ``conf/distro/poky.conf`` file in the ``meta-poky`` Git repository. 5292 5293 :term:`MLPREFIX` 5294 Specifies a prefix has been added to :term:`PN` to create a 5295 special version of a recipe or package (i.e. a Multilib version). The 5296 variable is used in places where the prefix needs to be added to or 5297 removed from a name (e.g. the :term:`BPN` variable). 5298 :term:`MLPREFIX` gets set when a prefix has been added to :term:`PN`. 5299 5300 .. note:: 5301 5302 The "ML" in :term:`MLPREFIX` stands for "MultiLib". This representation 5303 is historical and comes from a time when ":ref:`ref-classes-nativesdk`" 5304 was a suffix rather than a prefix on the recipe name. When 5305 ":ref:`ref-classes-nativesdk`" was turned into a prefix, it made sense 5306 to set :term:`MLPREFIX` for it as well. 5307 5308 To help understand when :term:`MLPREFIX` might be needed, consider when 5309 :term:`BBCLASSEXTEND` is used to provide a :ref:`ref-classes-nativesdk` 5310 version of a recipe in addition to the target version. If that recipe 5311 declares build-time dependencies on tasks in other recipes by using 5312 :term:`DEPENDS`, then a dependency on "foo" will automatically get 5313 rewritten to a dependency on "nativesdk-foo". However, dependencies like 5314 the following will not get rewritten automatically:: 5315 5316 do_foo[depends] += "recipe:do_foo" 5317 5318 If you want such a dependency to also get transformed, you can do the 5319 following:: 5320 5321 do_foo[depends] += "${MLPREFIX}recipe:do_foo" 5322 5323 :term:`module_autoload` 5324 This variable has been replaced by the :term:`KERNEL_MODULE_AUTOLOAD` 5325 variable. You should replace all occurrences of :term:`module_autoload` 5326 with additions to :term:`KERNEL_MODULE_AUTOLOAD`, for example:: 5327 5328 module_autoload_rfcomm = "rfcomm" 5329 5330 should now be replaced with:: 5331 5332 KERNEL_MODULE_AUTOLOAD += "rfcomm" 5333 5334 See the :term:`KERNEL_MODULE_AUTOLOAD` variable for more information. 5335 5336 :term:`module_conf` 5337 Specifies `modprobe.d <https://linux.die.net/man/5/modprobe.d>`__ 5338 syntax lines for inclusion in the ``/etc/modprobe.d/modname.conf`` 5339 file. 5340 5341 You can use this variable anywhere that it can be recognized by the 5342 kernel recipe or out-of-tree kernel module recipe (e.g. a machine 5343 configuration file, a distribution configuration file, an append file 5344 for the recipe, or the recipe itself). If you use this variable, you 5345 must also be sure to list the module name in the 5346 :term:`KERNEL_MODULE_PROBECONF` 5347 variable. 5348 5349 Here is the general syntax:: 5350 5351 module_conf_module_name = "modprobe.d-syntax" 5352 5353 You must use the kernel module name override. 5354 5355 Run ``man modprobe.d`` in the shell to find out more information on 5356 the exact syntax you want to provide with :term:`module_conf`. 5357 5358 Including :term:`module_conf` causes the OpenEmbedded build system to 5359 populate the ``/etc/modprobe.d/modname.conf`` file with 5360 ``modprobe.d`` syntax lines. Here is an example that adds the options 5361 ``arg1`` and ``arg2`` to a module named ``mymodule``:: 5362 5363 module_conf_mymodule = "options mymodule arg1=val1 arg2=val2" 5364 5365 For information on how to specify kernel modules to auto-load on 5366 boot, see the :term:`KERNEL_MODULE_AUTOLOAD` variable. 5367 5368 :term:`MODULE_TARBALL_DEPLOY` 5369 Controls creation of the ``modules-*.tgz`` file. Set this variable to 5370 "0" to disable creation of this file, which contains all of the 5371 kernel modules resulting from a kernel build. 5372 5373 :term:`MODULE_TARBALL_LINK_NAME` 5374 The link name of the kernel module tarball. This variable is set in 5375 the ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as follows:: 5376 5377 MODULE_TARBALL_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}" 5378 5379 The value 5380 of the ``KERNEL_ARTIFACT_LINK_NAME`` variable, which is set in the 5381 same file, has the following value:: 5382 5383 KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}" 5384 5385 See the :term:`MACHINE` variable for additional information. 5386 5387 :term:`MODULE_TARBALL_NAME` 5388 The base name of the kernel module tarball. This variable is set in 5389 the ``meta/classes-recipe/kernel-artifact-names.bbclass`` file as follows:: 5390 5391 MODULE_TARBALL_NAME ?= "${KERNEL_ARTIFACT_NAME}" 5392 5393 See :term:`KERNEL_ARTIFACT_NAME` for additional information. 5394 5395 :term:`MOUNT_BASE` 5396 On non-systemd systems (where ``udev-extraconf`` is being used), 5397 specifies the base directory for auto-mounting filesystems. The 5398 default value is "/run/media". 5399 5400 :term:`MULTIMACH_TARGET_SYS` 5401 Uniquely identifies the type of the target system for which packages 5402 are being built. This variable allows output for different types of 5403 target systems to be put into different subdirectories of the same 5404 output directory. 5405 5406 The default value of this variable is:: 5407 5408 ${PACKAGE_ARCH}${TARGET_VENDOR}-${TARGET_OS} 5409 5410 Some classes (e.g. :ref:`ref-classes-cross-canadian`) modify the 5411 :term:`MULTIMACH_TARGET_SYS` value. 5412 5413 See the :term:`STAMP` variable for an example. See the 5414 :term:`STAGING_DIR_TARGET` variable for more information. 5415 5416 :term:`NATIVELSBSTRING` 5417 A string identifying the host distribution. Strings consist of the 5418 host distributor ID followed by the release, as reported by the 5419 ``lsb_release`` tool or as read from ``/etc/lsb-release``. For 5420 example, when running a build on Ubuntu 12.10, the value is 5421 "Ubuntu-12.10". If this information is unable to be determined, the 5422 value resolves to "Unknown". 5423 5424 This variable is used by default to isolate native shared state 5425 packages for different distributions (e.g. to avoid problems with 5426 ``glibc`` version incompatibilities). Additionally, the variable is 5427 checked against 5428 :term:`SANITY_TESTED_DISTROS` if that 5429 variable is set. 5430 5431 :term:`NM` 5432 The minimal command and arguments to run ``nm``. 5433 5434 :term:`NO_GENERIC_LICENSE` 5435 Avoids QA errors when you use a non-common, non-CLOSED license in a 5436 recipe. There are packages, such as the linux-firmware package, with many 5437 licenses that are not in any way common. Also, new licenses are added 5438 occasionally to avoid introducing a lot of common license files, 5439 which are only applicable to a specific package. 5440 :term:`NO_GENERIC_LICENSE` is used to allow copying a license that does 5441 not exist in common licenses. 5442 5443 The following example shows how to add :term:`NO_GENERIC_LICENSE` to a 5444 recipe:: 5445 5446 NO_GENERIC_LICENSE[license_name] = "license_file_in_fetched_source" 5447 5448 Here is an example that 5449 uses the ``LICENSE.Abilis.txt`` file as the license from the fetched 5450 source:: 5451 5452 NO_GENERIC_LICENSE[Firmware-Abilis] = "LICENSE.Abilis.txt" 5453 5454 :term:`NO_RECOMMENDATIONS` 5455 Prevents installation of all "recommended-only" packages. 5456 Recommended-only packages are packages installed only through the 5457 :term:`RRECOMMENDS` variable). Setting the 5458 :term:`NO_RECOMMENDATIONS` variable to "1" turns this feature on:: 5459 5460 NO_RECOMMENDATIONS = "1" 5461 5462 You can set this variable globally in your ``local.conf`` file or you 5463 can attach it to a specific image recipe by using the recipe name 5464 override:: 5465 5466 NO_RECOMMENDATIONS:pn-target_image = "1" 5467 5468 It is important to realize that if you choose to not install packages 5469 using this variable and some other packages are dependent on them 5470 (i.e. listed in a recipe's :term:`RDEPENDS` 5471 variable), the OpenEmbedded build system ignores your request and 5472 will install the packages to avoid dependency errors. 5473 5474 .. note:: 5475 5476 Some recommended packages might be required for certain system 5477 functionality, such as kernel modules. It is up to you to add 5478 packages with the :term:`IMAGE_INSTALL` variable. 5479 5480 This variable is only supported when using the IPK and RPM 5481 packaging backends. DEB is not supported. 5482 5483 See the :term:`BAD_RECOMMENDATIONS` and 5484 the :term:`PACKAGE_EXCLUDE` variables for 5485 related information. 5486 5487 :term:`NOAUTOPACKAGEDEBUG` 5488 Disables auto package from splitting ``.debug`` files. If a recipe 5489 requires ``FILES:${PN}-dbg`` to be set manually, the 5490 :term:`NOAUTOPACKAGEDEBUG` can be defined allowing you to define the 5491 content of the debug package. For example:: 5492 5493 NOAUTOPACKAGEDEBUG = "1" 5494 FILES:${PN}-dev = "${includedir}/${QT_DIR_NAME}/Qt/*" 5495 FILES:${PN}-dbg = "/usr/src/debug/" 5496 FILES:${QT_BASE_NAME}-demos-doc = "${docdir}/${QT_DIR_NAME}/qch/qt.qch" 5497 5498 :term:`NON_MULTILIB_RECIPES` 5499 A list of recipes that should not be built for multilib. OE-Core's 5500 ``multilib.conf`` file defines a reasonable starting point for this 5501 list with:: 5502 5503 NON_MULTILIB_RECIPES = "grub grub-efi make-mod-scripts ovmf u-boot" 5504 5505 :term:`OBJCOPY` 5506 The minimal command and arguments to run ``objcopy``. 5507 5508 :term:`OBJDUMP` 5509 The minimal command and arguments to run ``objdump``. 5510 5511 :term:`OE_BINCONFIG_EXTRA_MANGLE` 5512 When inheriting the :ref:`ref-classes-binconfig` class, 5513 this variable specifies additional arguments passed to the "sed" 5514 command. The sed command alters any paths in configuration scripts 5515 that have been set up during compilation. Inheriting this class 5516 results in all paths in these scripts being changed to point into the 5517 ``sysroots/`` directory so that all builds that use the script will 5518 use the correct directories for the cross compiling layout. 5519 5520 See the ``meta/classes-recipe/binconfig.bbclass`` in the 5521 :term:`Source Directory` for details on how this class 5522 applies these additional sed command arguments. 5523 5524 :term:`OECMAKE_GENERATOR` 5525 A variable for the :ref:`ref-classes-cmake` class, allowing to choose 5526 which back-end will be generated by CMake to build an application. 5527 5528 By default, this variable is set to ``Ninja``, which is faster than GNU 5529 make, but if building is broken with Ninja, a recipe can use this 5530 variable to use GNU make instead:: 5531 5532 OECMAKE_GENERATOR = "Unix Makefiles" 5533 5534 :term:`OE_IMPORTS` 5535 An internal variable used to tell the OpenEmbedded build system what 5536 Python modules to import for every Python function run by the system. 5537 5538 .. note:: 5539 5540 Do not set this variable. It is for internal use only. 5541 5542 :term:`OE_INIT_ENV_SCRIPT` 5543 The name of the build environment setup script for the purposes of 5544 setting up the environment within the extensible SDK. The default 5545 value is "oe-init-build-env". 5546 5547 If you use a custom script to set up your build environment, set the 5548 :term:`OE_INIT_ENV_SCRIPT` variable to its name. 5549 5550 :term:`OE_TERMINAL` 5551 Controls how the OpenEmbedded build system spawns interactive 5552 terminals on the host development system (e.g. using the BitBake 5553 command with the ``-c devshell`` command-line option). For more 5554 information, see the ":ref:`dev-manual/development-shell:using a development shell`" section in 5555 the Yocto Project Development Tasks Manual. 5556 5557 You can use the following values for the :term:`OE_TERMINAL` variable: 5558 5559 - auto 5560 - gnome 5561 - xfce 5562 - rxvt 5563 - screen 5564 - konsole 5565 - none 5566 5567 :term:`OEROOT` 5568 The directory from which the top-level build environment setup script 5569 is sourced. The Yocto Project provides a top-level build environment 5570 setup script: :ref:`structure-core-script`. When you run this 5571 script, the :term:`OEROOT` variable resolves to the directory that 5572 contains the script. 5573 5574 For additional information on how this variable is used, see the 5575 initialization script. 5576 5577 :term:`OEQA_REPRODUCIBLE_TEST_TARGET` 5578 Set build target for build reproducibility testing. By default 5579 all available recipes are compiled with "bitbake world", see also :term:`EXCLUDE_FROM_WORLD` 5580 and :doc:`/test-manual/reproducible-builds`. 5581 5582 :term:`OEQA_REPRODUCIBLE_TEST_SSTATE_TARGETS` 5583 Set build targets which can be rebuilt using :ref:`shared state <overview-manual/concepts:shared state cache>` 5584 when running build reproducibility tests. See :doc:`/test-manual/reproducible-builds`. 5585 5586 :term:`OLDEST_KERNEL` 5587 Declares the oldest version of the Linux kernel that the produced 5588 binaries must support. This variable is passed into the build of the 5589 Embedded GNU C Library (``glibc``). 5590 5591 The default for this variable comes from the 5592 ``meta/conf/bitbake.conf`` configuration file. You can override this 5593 default by setting the variable in a custom distribution 5594 configuration file. 5595 5596 :term:`OVERLAYFS_ETC_DEVICE` 5597 When the :ref:`ref-classes-overlayfs-etc` class is 5598 inherited, specifies the device to be mounted for the read/write 5599 layer of ``/etc``. There is no default, so you must set this if you 5600 wish to enable :ref:`ref-classes-overlayfs-etc`, for 5601 example, assuming ``/dev/mmcblk0p2`` was the desired device:: 5602 5603 OVERLAYFS_ETC_DEVICE = "/dev/mmcblk0p2" 5604 5605 :term:`OVERLAYFS_ETC_EXPOSE_LOWER` 5606 When the :ref:`ref-classes-overlayfs-etc` class is 5607 inherited, if set to "1" then a read-only access to the original 5608 ``/etc`` content will be provided as a ``lower/`` subdirectory of 5609 :term:`OVERLAYFS_ETC_MOUNT_POINT`. The default value is "0". 5610 5611 :term:`OVERLAYFS_ETC_FSTYPE` 5612 When the :ref:`ref-classes-overlayfs-etc` class is 5613 inherited, specifies the file system type for the read/write 5614 layer of ``/etc``. There is no default, so you must set this if you 5615 wish to enable :ref:`ref-classes-overlayfs-etc`, 5616 for example, assuming the file system is ext4:: 5617 5618 OVERLAYFS_ETC_FSTYPE = "ext4" 5619 5620 :term:`OVERLAYFS_ETC_MOUNT_OPTIONS` 5621 When the :ref:`ref-classes-overlayfs-etc` class is 5622 inherited, specifies the mount options for the read-write layer. 5623 The default value is "defaults". 5624 5625 :term:`OVERLAYFS_ETC_MOUNT_POINT` 5626 When the :ref:`ref-classes-overlayfs-etc` class is 5627 inherited, specifies the parent mount path for the filesystem layers. 5628 There is no default, so you must set this if you wish to enable 5629 :ref:`ref-classes-overlayfs-etc`, for example if the desired path is 5630 "/data":: 5631 5632 OVERLAYFS_ETC_MOUNT_POINT = "/data" 5633 5634 :term:`OVERLAYFS_ETC_USE_ORIG_INIT_NAME` 5635 When the :ref:`ref-classes-overlayfs-etc` class is inherited, controls 5636 how the generated init will be named. For more information, see the 5637 :ref:`ref-classes-overlayfs-etc` class documentation. The default value 5638 is "1". 5639 5640 :term:`OVERLAYFS_MOUNT_POINT` 5641 When inheriting the :ref:`ref-classes-overlayfs` class, 5642 specifies mount point(s) to be used. For example:: 5643 5644 OVERLAYFS_MOUNT_POINT[data] = "/data" 5645 5646 The assumes you have a ``data.mount`` systemd unit defined elsewhere in 5647 your BSP (e.g. in ``systemd-machine-units`` recipe) and it is installed 5648 into the image. For more information see :ref:`ref-classes-overlayfs`. 5649 5650 .. note:: 5651 5652 Although the :ref:`ref-classes-overlayfs` class is 5653 inherited by individual recipes, :term:`OVERLAYFS_MOUNT_POINT` 5654 should be set in your machine configuration. 5655 5656 :term:`OVERLAYFS_QA_SKIP` 5657 When inheriting the :ref:`ref-classes-overlayfs` class, 5658 provides the ability to disable QA checks for particular overlayfs 5659 mounts. For example:: 5660 5661 OVERLAYFS_QA_SKIP[data] = "mount-configured" 5662 5663 .. note:: 5664 5665 Although the :ref:`ref-classes-overlayfs` class is 5666 inherited by individual recipes, :term:`OVERLAYFS_QA_SKIP` 5667 should be set in your machine configuration. 5668 5669 :term:`OVERLAYFS_WRITABLE_PATHS` 5670 When inheriting the :ref:`ref-classes-overlayfs` class, 5671 specifies writable paths used at runtime for the recipe. For 5672 example:: 5673 5674 OVERLAYFS_WRITABLE_PATHS[data] = "/usr/share/my-custom-application" 5675 5676 :term:`OVERRIDES` 5677 A colon-separated list of overrides that currently apply. Overrides 5678 are a BitBake mechanism that allows variables to be selectively 5679 overridden at the end of parsing. The set of overrides in 5680 :term:`OVERRIDES` represents the "state" during building, which includes 5681 the current recipe being built, the machine for which it is being 5682 built, and so forth. 5683 5684 As an example, if the string "an-override" appears as an element in 5685 the colon-separated list in :term:`OVERRIDES`, then the following 5686 assignment will override ``FOO`` with the value "overridden" at the 5687 end of parsing:: 5688 5689 FOO:an-override = "overridden" 5690 5691 See the 5692 ":ref:`bitbake-user-manual/bitbake-user-manual-metadata:conditional syntax (overrides)`" 5693 section in the BitBake User Manual for more information on the 5694 overrides mechanism. 5695 5696 The default value of :term:`OVERRIDES` includes the values of the 5697 :term:`CLASSOVERRIDE`, 5698 :term:`MACHINEOVERRIDES`, and 5699 :term:`DISTROOVERRIDES` variables. Another 5700 important override included by default is ``pn-${PN}``. This override 5701 allows variables to be set for a single recipe within configuration 5702 (``.conf``) files. Here is an example:: 5703 5704 FOO:pn-myrecipe = "myrecipe-specific value" 5705 5706 .. note:: 5707 5708 An easy way to see what overrides apply is to search for :term:`OVERRIDES` 5709 in the output of the ``bitbake -e`` command. See the 5710 ":ref:`dev-manual/debugging:viewing variable values`" section in the Yocto 5711 Project Development Tasks Manual for more information. 5712 5713 :term:`P` 5714 The recipe name and version. :term:`P` is comprised of the following:: 5715 5716 ${PN}-${PV} 5717 5718 :term:`P4DIR` 5719 See :term:`bitbake:P4DIR` in the BitBake manual. 5720 5721 :term:`PACKAGE_ADD_METADATA` 5722 This variable defines additional metadata to add to packages. 5723 5724 You may find you need to inject additional metadata into packages. 5725 This variable allows you to do that by setting the injected data as 5726 the value. Multiple fields can be added by splitting the content with 5727 the literal separator "\n". 5728 5729 The suffixes '_IPK', '_DEB', or '_RPM' can be applied to the variable 5730 to do package type specific settings. It can also be made package 5731 specific by using the package name as a suffix. 5732 5733 You can find out more about applying this variable in the 5734 ":ref:`dev-manual/packages:adding custom metadata to packages`" 5735 section in the Yocto Project Development Tasks Manual. 5736 5737 :term:`PACKAGE_ARCH` 5738 The architecture of the resulting package or packages. 5739 5740 By default, the value of this variable is set to 5741 :term:`TUNE_PKGARCH` when building for the 5742 target, :term:`BUILD_ARCH` when building for the 5743 build host, and "${SDK_ARCH}-${SDKPKGSUFFIX}" when building for the 5744 SDK. 5745 5746 .. note:: 5747 5748 See :term:`SDK_ARCH` for more information. 5749 5750 However, if your recipe's output packages are built specific to the 5751 target machine rather than generally for the architecture of the 5752 machine, you should set :term:`PACKAGE_ARCH` to the value of 5753 :term:`MACHINE_ARCH` in the recipe as follows:: 5754 5755 PACKAGE_ARCH = "${MACHINE_ARCH}" 5756 5757 :term:`PACKAGE_ARCHS` 5758 Specifies a list of architectures compatible with the target machine. 5759 This variable is set automatically and should not normally be 5760 hand-edited. Entries are separated using spaces and listed in order 5761 of priority. The default value for :term:`PACKAGE_ARCHS` is "all any 5762 noarch ${PACKAGE_EXTRA_ARCHS} ${MACHINE_ARCH}". 5763 5764 :term:`PACKAGE_BEFORE_PN` 5765 Enables easily adding packages to :term:`PACKAGES` before ``${PN}`` so 5766 that those added packages can pick up files that would normally be 5767 included in the default package. 5768 5769 :term:`PACKAGE_CLASSES` 5770 This variable, which is set in the ``local.conf`` configuration file 5771 found in the ``conf`` folder of the 5772 :term:`Build Directory`, specifies the package manager the 5773 OpenEmbedded build system uses when packaging data. 5774 5775 You can provide one or more of the following arguments for the 5776 variable:: 5777 5778 PACKAGE_CLASSES ?= "package_rpm package_deb package_ipk" 5779 5780 The build system uses only the first argument in the list as the 5781 package manager when creating your image or SDK. However, packages 5782 will be created using any additional packaging classes you specify. 5783 For example, if you use the following in your ``local.conf`` file:: 5784 5785 PACKAGE_CLASSES ?= "package_ipk" 5786 5787 The OpenEmbedded build system uses 5788 the IPK package manager to create your image or SDK. 5789 5790 For information on packaging and build performance effects as a 5791 result of the package manager in use, see the 5792 ":ref:`ref-classes-package`" section. 5793 5794 :term:`PACKAGE_DEBUG_SPLIT_STYLE` 5795 Determines how to split up and package debug and source information 5796 when creating debugging packages to be used with the GNU Project 5797 Debugger (GDB). In general, based on the value of this variable, 5798 you can combine the source and debug info in a single package, 5799 you can break out the source into a separate package that can be 5800 installed independently, or you can choose to not have the source 5801 packaged at all. 5802 5803 The possible values of :term:`PACKAGE_DEBUG_SPLIT_STYLE` variable: 5804 5805 - "``.debug``": All debugging and source info is placed in a single 5806 ``*-dbg`` package; debug symbol files are placed next to the 5807 binary in a ``.debug`` directory so that, if a binary is installed 5808 into ``/bin``, the corresponding debug symbol file is installed 5809 in ``/bin/.debug``. Source files are installed in the same ``*-dbg`` 5810 package under ``/usr/src/debug``. 5811 5812 - "``debug-file-directory``": As above, all debugging and source info 5813 is placed in a single ``*-dbg`` package; debug symbol files are 5814 placed entirely under the directory ``/usr/lib/debug`` and separated 5815 by the path from where the binary is installed, so that if a binary 5816 is installed in ``/bin``, the corresponding debug symbols are installed 5817 in ``/usr/lib/debug/bin``, and so on. As above, source is installed 5818 in the same package under ``/usr/src/debug``. 5819 5820 - "``debug-with-srcpkg``": Debugging info is placed in the standard 5821 ``*-dbg`` package as with the ``.debug`` value, while source is 5822 placed in a separate ``*-src`` package, which can be installed 5823 independently. This is the default setting for this variable, 5824 as defined in Poky's ``bitbake.conf`` file. 5825 5826 - "``debug-without-src``": The same behavior as with the ``.debug`` 5827 setting, but no source is packaged at all. 5828 5829 .. note:: 5830 5831 Much of the above package splitting can be overridden via 5832 use of the :term:`INHIBIT_PACKAGE_DEBUG_SPLIT` variable. 5833 5834 You can find out more about debugging using GDB by reading the 5835 ":ref:`dev-manual/debugging:debugging with the gnu project debugger (gdb) remotely`" section 5836 in the Yocto Project Development Tasks Manual. 5837 5838 :term:`PACKAGE_EXCLUDE` 5839 Lists packages that should not be installed into an image. For 5840 example:: 5841 5842 PACKAGE_EXCLUDE = "package_name package_name package_name ..." 5843 5844 You can set this variable globally in your ``local.conf`` file or you 5845 can attach it to a specific image recipe by using the recipe name 5846 override:: 5847 5848 PACKAGE_EXCLUDE:pn-target_image = "package_name" 5849 5850 If you choose to not install a package using this variable and some 5851 other package is dependent on it (i.e. listed in a recipe's 5852 :term:`RDEPENDS` variable), the OpenEmbedded build 5853 system generates a fatal installation error. Because the build system 5854 halts the process with a fatal error, you can use the variable with 5855 an iterative development process to remove specific components from a 5856 system. 5857 5858 This variable is supported only when using the IPK and RPM 5859 packaging backends. DEB is not supported. 5860 5861 See the :term:`NO_RECOMMENDATIONS` and the 5862 :term:`BAD_RECOMMENDATIONS` variables for 5863 related information. 5864 5865 :term:`PACKAGE_EXCLUDE_COMPLEMENTARY` 5866 Prevents specific packages from being installed when you are 5867 installing complementary packages. 5868 5869 You might find that you want to prevent installing certain packages 5870 when you are installing complementary packages. For example, if you 5871 are using :term:`IMAGE_FEATURES` to install 5872 ``dev-pkgs``, you might not want to install all packages from a 5873 particular multilib. If you find yourself in this situation, you can 5874 use the :term:`PACKAGE_EXCLUDE_COMPLEMENTARY` variable to specify regular 5875 expressions to match the packages you want to exclude. 5876 5877 :term:`PACKAGE_EXTRA_ARCHS` 5878 Specifies the list of architectures compatible with the device CPU. 5879 This variable is useful when you build for several different devices 5880 that use miscellaneous processors such as XScale and ARM926-EJS. 5881 5882 :term:`PACKAGE_FEED_ARCHS` 5883 Optionally specifies the package architectures used as part of the 5884 package feed URIs during the build. When used, the 5885 :term:`PACKAGE_FEED_ARCHS` variable is appended to the final package feed 5886 URI, which is constructed using the 5887 :term:`PACKAGE_FEED_URIS` and 5888 :term:`PACKAGE_FEED_BASE_PATHS` 5889 variables. 5890 5891 .. note:: 5892 5893 You can use the :term:`PACKAGE_FEED_ARCHS` 5894 variable to allow specific package architectures. If you do 5895 not need to allow specific architectures, which is a common 5896 case, you can omit this variable. Omitting the variable results in 5897 all available architectures for the current machine being included 5898 into remote package feeds. 5899 5900 Consider the following example where the :term:`PACKAGE_FEED_URIS`, 5901 :term:`PACKAGE_FEED_BASE_PATHS`, and :term:`PACKAGE_FEED_ARCHS` variables are 5902 defined in your ``local.conf`` file:: 5903 5904 PACKAGE_FEED_URIS = "https://example.com/packagerepos/release \ 5905 https://example.com/packagerepos/updates" 5906 PACKAGE_FEED_BASE_PATHS = "rpm rpm-dev" 5907 PACKAGE_FEED_ARCHS = "all core2-64" 5908 5909 Given these settings, the resulting package feeds are as follows: 5910 5911 .. code-block:: none 5912 5913 https://example.com/packagerepos/release/rpm/all 5914 https://example.com/packagerepos/release/rpm/core2-64 5915 https://example.com/packagerepos/release/rpm-dev/all 5916 https://example.com/packagerepos/release/rpm-dev/core2-64 5917 https://example.com/packagerepos/updates/rpm/all 5918 https://example.com/packagerepos/updates/rpm/core2-64 5919 https://example.com/packagerepos/updates/rpm-dev/all 5920 https://example.com/packagerepos/updates/rpm-dev/core2-64 5921 5922 :term:`PACKAGE_FEED_BASE_PATHS` 5923 Specifies the base path used when constructing package feed URIs. The 5924 :term:`PACKAGE_FEED_BASE_PATHS` variable makes up the middle portion of a 5925 package feed URI used by the OpenEmbedded build system. The base path 5926 lies between the :term:`PACKAGE_FEED_URIS` 5927 and :term:`PACKAGE_FEED_ARCHS` variables. 5928 5929 Consider the following example where the :term:`PACKAGE_FEED_URIS`, 5930 :term:`PACKAGE_FEED_BASE_PATHS`, and :term:`PACKAGE_FEED_ARCHS` variables are 5931 defined in your ``local.conf`` file:: 5932 5933 PACKAGE_FEED_URIS = "https://example.com/packagerepos/release \ 5934 https://example.com/packagerepos/updates" 5935 PACKAGE_FEED_BASE_PATHS = "rpm rpm-dev" 5936 PACKAGE_FEED_ARCHS = "all core2-64" 5937 5938 Given these settings, the resulting package feeds are as follows: 5939 5940 .. code-block:: none 5941 5942 https://example.com/packagerepos/release/rpm/all 5943 https://example.com/packagerepos/release/rpm/core2-64 5944 https://example.com/packagerepos/release/rpm-dev/all 5945 https://example.com/packagerepos/release/rpm-dev/core2-64 5946 https://example.com/packagerepos/updates/rpm/all 5947 https://example.com/packagerepos/updates/rpm/core2-64 5948 https://example.com/packagerepos/updates/rpm-dev/all 5949 https://example.com/packagerepos/updates/rpm-dev/core2-64 5950 5951 :term:`PACKAGE_FEED_URIS` 5952 Specifies the front portion of the package feed URI used by the 5953 OpenEmbedded build system. Each final package feed URI is comprised 5954 of :term:`PACKAGE_FEED_URIS`, 5955 :term:`PACKAGE_FEED_BASE_PATHS`, and 5956 :term:`PACKAGE_FEED_ARCHS` variables. 5957 5958 Consider the following example where the :term:`PACKAGE_FEED_URIS`, 5959 :term:`PACKAGE_FEED_BASE_PATHS`, and :term:`PACKAGE_FEED_ARCHS` variables are 5960 defined in your ``local.conf`` file:: 5961 5962 PACKAGE_FEED_URIS = "https://example.com/packagerepos/release \ 5963 https://example.com/packagerepos/updates" 5964 PACKAGE_FEED_BASE_PATHS = "rpm rpm-dev" 5965 PACKAGE_FEED_ARCHS = "all core2-64" 5966 5967 Given these settings, the resulting package feeds are as follows: 5968 5969 .. code-block:: none 5970 5971 https://example.com/packagerepos/release/rpm/all 5972 https://example.com/packagerepos/release/rpm/core2-64 5973 https://example.com/packagerepos/release/rpm-dev/all 5974 https://example.com/packagerepos/release/rpm-dev/core2-64 5975 https://example.com/packagerepos/updates/rpm/all 5976 https://example.com/packagerepos/updates/rpm/core2-64 5977 https://example.com/packagerepos/updates/rpm-dev/all 5978 https://example.com/packagerepos/updates/rpm-dev/core2-64 5979 5980 :term:`PACKAGE_INSTALL` 5981 The final list of packages passed to the package manager for 5982 installation into the image. 5983 5984 Because the package manager controls actual installation of all 5985 packages, the list of packages passed using :term:`PACKAGE_INSTALL` is 5986 not the final list of packages that are actually installed. This 5987 variable is internal to the image construction code. Consequently, in 5988 general, you should use the 5989 :term:`IMAGE_INSTALL` variable to specify 5990 packages for installation. The exception to this is when working with 5991 the :ref:`core-image-minimal-initramfs <ref-manual/images:images>` 5992 image. When working with an initial RAM filesystem (:term:`Initramfs`) image, 5993 use the :term:`PACKAGE_INSTALL` variable. For information on creating an 5994 :term:`Initramfs`, see the ":ref:`dev-manual/building:building an initial ram filesystem (Initramfs) image`" section 5995 in the Yocto Project Development Tasks Manual. 5996 5997 :term:`PACKAGE_INSTALL_ATTEMPTONLY` 5998 Specifies a list of packages the OpenEmbedded build system attempts 5999 to install when creating an image. If a listed package fails to 6000 install, the build system does not generate an error. This variable 6001 is generally not user-defined. 6002 6003 :term:`PACKAGE_PREPROCESS_FUNCS` 6004 Specifies a list of functions run to pre-process the 6005 :term:`PKGD` directory prior to splitting the files out 6006 to individual packages. 6007 6008 :term:`PACKAGE_WRITE_DEPS` 6009 Specifies a list of dependencies for post-installation and 6010 pre-installation scripts on native/cross tools. If your 6011 post-installation or pre-installation script can execute at root filesystem 6012 creation time rather than on the target but depends on a native tool 6013 in order to execute, you need to list the tools in 6014 :term:`PACKAGE_WRITE_DEPS`. 6015 6016 For information on running post-installation scripts, see the 6017 ":ref:`dev-manual/new-recipe:post-installation scripts`" 6018 section in the Yocto Project Development Tasks Manual. 6019 6020 :term:`PACKAGECONFIG` 6021 This variable provides a means of enabling or disabling features of a 6022 recipe on a per-recipe basis. :term:`PACKAGECONFIG` blocks are defined in 6023 recipes when you specify features and then arguments that define 6024 feature behaviors. Here is the basic block structure (broken over 6025 multiple lines for readability):: 6026 6027 PACKAGECONFIG ??= "f1 f2 f3 ..." 6028 PACKAGECONFIG[f1] = "\ 6029 --with-f1, \ 6030 --without-f1, \ 6031 build-deps-for-f1, \ 6032 runtime-deps-for-f1, \ 6033 runtime-recommends-for-f1, \ 6034 packageconfig-conflicts-for-f1" 6035 PACKAGECONFIG[f2] = "\ 6036 ... and so on and so on ... 6037 6038 The :term:`PACKAGECONFIG` variable itself specifies a space-separated 6039 list of the features to enable. Following the features, you can 6040 determine the behavior of each feature by providing up to six 6041 order-dependent arguments, which are separated by commas. You can 6042 omit any argument you like but must retain the separating commas. The 6043 order is important and specifies the following: 6044 6045 #. Extra arguments that should be added to the configure script 6046 argument list (:term:`EXTRA_OECONF` or 6047 :term:`PACKAGECONFIG_CONFARGS`) if 6048 the feature is enabled. 6049 6050 #. Extra arguments that should be added to :term:`EXTRA_OECONF` or 6051 :term:`PACKAGECONFIG_CONFARGS` if the feature is disabled. 6052 6053 #. Additional build dependencies (:term:`DEPENDS`) 6054 that should be added if the feature is enabled. 6055 6056 #. Additional runtime dependencies (:term:`RDEPENDS`) 6057 that should be added if the feature is enabled. 6058 6059 #. Additional runtime recommendations 6060 (:term:`RRECOMMENDS`) that should be added if 6061 the feature is enabled. 6062 6063 #. Any conflicting (that is, mutually exclusive) :term:`PACKAGECONFIG` 6064 settings for this feature. 6065 6066 Consider the following :term:`PACKAGECONFIG` block taken from the 6067 ``librsvg`` recipe. In this example the feature is ``gtk``, which has 6068 three arguments that determine the feature's behavior:: 6069 6070 PACKAGECONFIG[gtk] = "--with-gtk3,--without-gtk3,gtk+3" 6071 6072 The 6073 ``--with-gtk3`` and ``gtk+3`` arguments apply only if the feature is 6074 enabled. In this case, ``--with-gtk3`` is added to the configure 6075 script argument list and ``gtk+3`` is added to :term:`DEPENDS`. On the 6076 other hand, if the feature is disabled say through a ``.bbappend`` 6077 file in another layer, then the second argument ``--without-gtk3`` is 6078 added to the configure script instead. 6079 6080 The basic :term:`PACKAGECONFIG` structure previously described holds true 6081 regardless of whether you are creating a block or changing a block. 6082 When creating a block, use the structure inside your recipe. 6083 6084 If you want to change an existing :term:`PACKAGECONFIG` block, you can do 6085 so one of two ways: 6086 6087 - *Append file:* Create an append file named 6088 ``recipename.bbappend`` in your layer and override the value of 6089 :term:`PACKAGECONFIG`. You can either completely override the 6090 variable:: 6091 6092 PACKAGECONFIG = "f4 f5" 6093 6094 Or, you can just append the variable:: 6095 6096 PACKAGECONFIG:append = " f4" 6097 6098 - *Configuration file:* This method is identical to changing the 6099 block through an append file except you edit your ``local.conf`` 6100 or ``mydistro.conf`` file. As with append files previously 6101 described, you can either completely override the variable:: 6102 6103 PACKAGECONFIG:pn-recipename = "f4 f5" 6104 6105 Or, you can just amend the variable:: 6106 6107 PACKAGECONFIG:append:pn-recipename = " f4" 6108 6109 :term:`PACKAGECONFIG_CONFARGS` 6110 A space-separated list of configuration options generated from the 6111 :term:`PACKAGECONFIG` setting. 6112 6113 Classes such as :ref:`ref-classes-autotools` and :ref:`ref-classes-cmake` 6114 use :term:`PACKAGECONFIG_CONFARGS` to pass :term:`PACKAGECONFIG` options 6115 to ``configure`` and ``cmake``, respectively. If you are using 6116 :term:`PACKAGECONFIG` but not a class that handles the 6117 :ref:`ref-tasks-configure` task, then you need to use 6118 :term:`PACKAGECONFIG_CONFARGS` appropriately. 6119 6120 :term:`PACKAGEGROUP_DISABLE_COMPLEMENTARY` 6121 For recipes inheriting the :ref:`ref-classes-packagegroup` class, setting 6122 :term:`PACKAGEGROUP_DISABLE_COMPLEMENTARY` to "1" specifies that the 6123 normal complementary packages (i.e. ``-dev``, ``-dbg``, and so forth) 6124 should not be automatically created by the ``packagegroup`` recipe, 6125 which is the default behavior. 6126 6127 :term:`PACKAGES` 6128 The list of packages the recipe creates. The default value is the 6129 following:: 6130 6131 ${PN}-src ${PN}-dbg ${PN}-staticdev ${PN}-dev ${PN}-doc ${PN}-locale ${PACKAGE_BEFORE_PN} ${PN} 6132 6133 During packaging, the :ref:`ref-tasks-package` task 6134 goes through :term:`PACKAGES` and uses the :term:`FILES` 6135 variable corresponding to each package to assign files to the 6136 package. If a file matches the :term:`FILES` variable for more than one 6137 package in :term:`PACKAGES`, it will be assigned to the earliest 6138 (leftmost) package. 6139 6140 Packages in the variable's list that are empty (i.e. where none of 6141 the patterns in ``FILES:``\ pkg match any files installed by the 6142 :ref:`ref-tasks-install` task) are not generated, 6143 unless generation is forced through the 6144 :term:`ALLOW_EMPTY` variable. 6145 6146 :term:`PACKAGES_DYNAMIC` 6147 A promise that your recipe satisfies runtime dependencies for 6148 optional modules that are found in other recipes. 6149 :term:`PACKAGES_DYNAMIC` does not actually satisfy the dependencies, it 6150 only states that they should be satisfied. For example, if a hard, 6151 runtime dependency (:term:`RDEPENDS`) of another 6152 package is satisfied at build time through the :term:`PACKAGES_DYNAMIC` 6153 variable, but a package with the module name is never actually 6154 produced, then the other package will be broken. Thus, if you attempt 6155 to include that package in an image, you will get a dependency 6156 failure from the packaging system during the 6157 :ref:`ref-tasks-rootfs` task. 6158 6159 Typically, if there is a chance that such a situation can occur and 6160 the package that is not created is valid without the dependency being 6161 satisfied, then you should use :term:`RRECOMMENDS` 6162 (a soft runtime dependency) instead of :term:`RDEPENDS`. 6163 6164 For an example of how to use the :term:`PACKAGES_DYNAMIC` variable when 6165 you are splitting packages, see the 6166 ":ref:`dev-manual/packages:handling optional module packaging`" 6167 section in the Yocto Project Development Tasks Manual. 6168 6169 :term:`PACKAGESPLITFUNCS` 6170 Specifies a list of functions run to perform additional splitting of 6171 files into individual packages. Recipes can either prepend to this 6172 variable or prepend to the ``populate_packages`` function in order to 6173 perform additional package splitting. In either case, the function 6174 should set :term:`PACKAGES`, 6175 :term:`FILES`, :term:`RDEPENDS` and 6176 other packaging variables appropriately in order to perform the 6177 desired splitting. 6178 6179 :term:`PARALLEL_MAKE` 6180 6181 Extra options passed to the build tool command (``make``, 6182 ``ninja`` or more specific build engines, like the Go language one) 6183 during the :ref:`ref-tasks-compile` task, to specify parallel compilation 6184 on the local build host. This variable is usually in the form "-j x", 6185 where x represents the maximum number of parallel threads such engines 6186 can run. 6187 6188 .. note:: 6189 6190 For software compiled by ``make``, in order for :term:`PARALLEL_MAKE` 6191 to be effective, ``make`` must be called with 6192 ``${``\ :term:`EXTRA_OEMAKE`\ ``}``. An easy 6193 way to ensure this is to use the ``oe_runmake`` function. 6194 6195 By default, the OpenEmbedded build system automatically sets this 6196 variable to be equal to the number of cores the build system uses. 6197 6198 .. note:: 6199 6200 If the software being built experiences dependency issues during 6201 the :ref:`ref-tasks-compile` task that result in race conditions, you can clear 6202 the :term:`PARALLEL_MAKE` variable within the recipe as a workaround. For 6203 information on addressing race conditions, see the 6204 ":ref:`dev-manual/debugging:debugging parallel make races`" 6205 section in the Yocto Project Development Tasks Manual. 6206 6207 For single socket systems (i.e. one CPU), you should not have to 6208 override this variable to gain optimal parallelism during builds. 6209 However, if you have very large systems that employ multiple physical 6210 CPUs, you might want to make sure the :term:`PARALLEL_MAKE` variable is 6211 not set higher than "-j 20". 6212 6213 For more information on speeding up builds, see the 6214 ":ref:`dev-manual/speeding-up-build:speeding up a build`" 6215 section in the Yocto Project Development Tasks Manual. 6216 6217 :term:`PARALLEL_MAKEINST` 6218 Extra options passed to the build tool install command 6219 (``make install``, ``ninja install`` or more specific ones) 6220 during the :ref:`ref-tasks-install` task in order to specify 6221 parallel installation. This variable defaults to the value of 6222 :term:`PARALLEL_MAKE`. 6223 6224 .. note:: 6225 6226 For software compiled by ``make``, in order for :term:`PARALLEL_MAKEINST` 6227 to be effective, ``make`` must be called with 6228 ``${``\ :term:`EXTRA_OEMAKE`\ ``}``. An easy 6229 way to ensure this is to use the ``oe_runmake`` function. 6230 6231 If the software being built experiences dependency issues during 6232 the :ref:`ref-tasks-install` task that result in race conditions, you can 6233 clear the :term:`PARALLEL_MAKEINST` variable within the recipe as a 6234 workaround. For information on addressing race conditions, see the 6235 ":ref:`dev-manual/debugging:debugging parallel make races`" 6236 section in the Yocto Project Development Tasks Manual. 6237 6238 :term:`PATCHRESOLVE` 6239 Determines the action to take when a patch fails. You can set this 6240 variable to one of two values: "noop" and "user". 6241 6242 The default value of "noop" causes the build to simply fail when the 6243 OpenEmbedded build system cannot successfully apply a patch. Setting 6244 the value to "user" causes the build system to launch a shell and 6245 places you in the right location so that you can manually resolve the 6246 conflicts. 6247 6248 Set this variable in your ``local.conf`` file. 6249 6250 :term:`PATCHTOOL` 6251 Specifies the utility used to apply patches for a recipe during the 6252 :ref:`ref-tasks-patch` task. You can specify one of 6253 three utilities: "patch", "quilt", or "git". The default utility used 6254 is "quilt" except for the quilt-native recipe itself. Because the 6255 quilt tool is not available at the time quilt-native is being 6256 patched, it uses "patch". 6257 6258 If you wish to use an alternative patching tool, set the variable in 6259 the recipe using one of the following:: 6260 6261 PATCHTOOL = "patch" 6262 PATCHTOOL = "quilt" 6263 PATCHTOOL = "git" 6264 6265 :term:`PE` 6266 The epoch of the recipe. By default, this variable is unset. The 6267 variable is used to make upgrades possible when the versioning scheme 6268 changes in some backwards incompatible way. 6269 6270 :term:`PE` is the default value of the :term:`PKGE` variable. 6271 6272 :term:`PEP517_WHEEL_PATH` 6273 When used by recipes that inherit the :ref:`ref-classes-python_pep517` 6274 class, denotes the path to ``dist/`` (short for distribution) where the 6275 binary archive ``wheel`` is built. 6276 6277 :term:`PERSISTENT_DIR` 6278 See :term:`bitbake:PERSISTENT_DIR` in the BitBake manual. 6279 6280 :term:`PF` 6281 Specifies the recipe or package name and includes all version and 6282 revision numbers (i.e. ``glibc-2.13-r20+svnr15508/`` and 6283 ``bash-4.2-r1/``). This variable is comprised of the following: 6284 ${:term:`PN`}-${:term:`EXTENDPE`}${:term:`PV`}-${:term:`PR`} 6285 6286 :term:`PIXBUF_PACKAGES` 6287 When inheriting the :ref:`ref-classes-pixbufcache` 6288 class, this variable identifies packages that contain the pixbuf 6289 loaders used with ``gdk-pixbuf``. By default, the 6290 :ref:`ref-classes-pixbufcache` class assumes that 6291 the loaders are in the recipe's main package (i.e. 6292 ``${``\ :term:`PN`\ ``}``). Use this variable if the 6293 loaders you need are in a package other than that main package. 6294 6295 :term:`PKG` 6296 The name of the resulting package created by the OpenEmbedded build 6297 system. 6298 6299 .. note:: 6300 6301 When using the :term:`PKG` variable, you must use a package name override. 6302 6303 For example, when the :ref:`ref-classes-debian` class renames the output 6304 package, it does so by setting ``PKG:packagename``. 6305 6306 :term:`PKG_CONFIG_PATH` 6307 The path to ``pkg-config`` files for the current build context. 6308 ``pkg-config`` reads this variable from the environment. 6309 6310 :term:`PKGD` 6311 Points to the destination directory for files to be packaged before 6312 they are split into individual packages. This directory defaults to 6313 the following:: 6314 6315 ${WORKDIR}/package 6316 6317 Do not change this default. 6318 6319 :term:`PKGDATA_DIR` 6320 Points to a shared, global-state directory that holds data generated 6321 during the packaging process. During the packaging process, the 6322 :ref:`ref-tasks-packagedata` task packages data 6323 for each recipe and installs it into this temporary, shared area. 6324 This directory defaults to the following, which you should not 6325 change:: 6326 6327 ${STAGING_DIR_HOST}/pkgdata 6328 6329 For examples of how this data is used, see the 6330 ":ref:`overview-manual/concepts:automatically added runtime dependencies`" 6331 section in the Yocto Project Overview and Concepts Manual and the 6332 ":ref:`dev-manual/debugging:viewing package information with \`\`oe-pkgdata-util\`\``" 6333 section in the Yocto Project Development Tasks Manual. For more 6334 information on the shared, global-state directory, see 6335 :term:`STAGING_DIR_HOST`. 6336 6337 :term:`PKGDEST` 6338 Points to the parent directory for files to be packaged after they 6339 have been split into individual packages. This directory defaults to 6340 the following:: 6341 6342 ${WORKDIR}/packages-split 6343 6344 Under this directory, the build system creates directories for each 6345 package specified in :term:`PACKAGES`. Do not change 6346 this default. 6347 6348 :term:`PKGDESTWORK` 6349 Points to a temporary work area where the 6350 :ref:`ref-tasks-package` task saves package metadata. 6351 The :term:`PKGDESTWORK` location defaults to the following:: 6352 6353 ${WORKDIR}/pkgdata 6354 6355 Do not change this default. 6356 6357 The :ref:`ref-tasks-packagedata` task copies the 6358 package metadata from :term:`PKGDESTWORK` to 6359 :term:`PKGDATA_DIR` to make it available globally. 6360 6361 :term:`PKGE` 6362 The epoch of the package(s) built by the recipe. By default, :term:`PKGE` 6363 is set to :term:`PE`. 6364 6365 :term:`PKGR` 6366 The revision of the package(s) built by the recipe. By default, 6367 :term:`PKGR` is set to :term:`PR`. 6368 6369 :term:`PKGV` 6370 The version of the package(s) built by the recipe. By default, 6371 :term:`PKGV` is set to :term:`PV`. 6372 6373 :term:`PN` 6374 This variable can have two separate functions depending on the 6375 context: a recipe name or a resulting package name. 6376 6377 :term:`PN` refers to a recipe name in the context of a file used by the 6378 OpenEmbedded build system as input to create a package. The name is 6379 normally extracted from the recipe file name. For example, if the 6380 recipe is named ``expat_2.0.1.bb``, then the default value of :term:`PN` 6381 will be "expat". 6382 6383 The variable refers to a package name in the context of a file 6384 created or produced by the OpenEmbedded build system. 6385 6386 If applicable, the :term:`PN` variable also contains any special suffix 6387 or prefix. For example, using ``bash`` to build packages for the 6388 native machine, :term:`PN` is ``bash-native``. Using ``bash`` to build 6389 packages for the target and for Multilib, :term:`PN` would be ``bash`` 6390 and ``lib64-bash``, respectively. 6391 6392 :term:`POPULATE_SDK_POST_HOST_COMMAND` 6393 Specifies a list of functions to call once the OpenEmbedded build 6394 system has created the host part of the SDK. You can specify 6395 functions separated by semicolons:: 6396 6397 POPULATE_SDK_POST_HOST_COMMAND += "function; ... " 6398 6399 If you need to pass the SDK path to a command within a function, you 6400 can use ``${SDK_DIR}``, which points to the parent directory used by 6401 the OpenEmbedded build system when creating SDK output. See the 6402 :term:`SDK_DIR` variable for more information. 6403 6404 :term:`POPULATE_SDK_POST_TARGET_COMMAND` 6405 Specifies a list of functions to call once the OpenEmbedded build 6406 system has created the target part of the SDK. You can specify 6407 functions separated by semicolons:: 6408 6409 POPULATE_SDK_POST_TARGET_COMMAND += "function; ... " 6410 6411 If you need to pass the SDK path to a command within a function, you 6412 can use ``${SDK_DIR}``, which points to the parent directory used by 6413 the OpenEmbedded build system when creating SDK output. See the 6414 :term:`SDK_DIR` variable for more information. 6415 6416 :term:`PR` 6417 The revision of the recipe. The default value for this variable is 6418 "r0". Subsequent revisions of the recipe conventionally have the 6419 values "r1", "r2", and so forth. When :term:`PV` increases, 6420 :term:`PR` is conventionally reset to "r0". 6421 6422 .. note:: 6423 6424 The OpenEmbedded build system does not need the aid of :term:`PR` 6425 to know when to rebuild a recipe. The build system uses the task 6426 :ref:`input checksums <overview-manual/concepts:checksums (signatures)>` along with the 6427 :ref:`stamp <structure-build-tmp-stamps>` and 6428 :ref:`overview-manual/concepts:shared state cache` 6429 mechanisms. 6430 6431 The :term:`PR` variable primarily becomes significant when a package 6432 manager dynamically installs packages on an already built image. In 6433 this case, :term:`PR`, which is the default value of 6434 :term:`PKGR`, helps the package manager distinguish which 6435 package is the most recent one in cases where many packages have the 6436 same :term:`PV` (i.e. :term:`PKGV`). A component having many packages with 6437 the same :term:`PV` usually means that the packages all install the same 6438 upstream version, but with later (:term:`PR`) version packages including 6439 packaging fixes. 6440 6441 .. note:: 6442 6443 :term:`PR` does not need to be increased for changes that do not change the 6444 package contents or metadata. 6445 6446 Because manually managing :term:`PR` can be cumbersome and error-prone, 6447 an automated solution exists. See the 6448 ":ref:`dev-manual/packages:working with a pr service`" section 6449 in the Yocto Project Development Tasks Manual for more information. 6450 6451 :term:`PREFERRED_PROVIDER` 6452 If multiple recipes provide the same item, this variable determines 6453 which recipe is preferred and thus provides the item (i.e. the 6454 preferred provider). You should always suffix this variable with the 6455 name of the provided item. And, you should define the variable using 6456 the preferred recipe's name (:term:`PN`). Here is a common 6457 example:: 6458 6459 PREFERRED_PROVIDER_virtual/kernel ?= "linux-yocto" 6460 6461 In the previous example, multiple recipes are providing "virtual/kernel". 6462 The :term:`PREFERRED_PROVIDER` variable is set with the name (:term:`PN`) of 6463 the recipe you prefer to provide "virtual/kernel". 6464 6465 Following are more examples:: 6466 6467 PREFERRED_PROVIDER_virtual/xserver = "xserver-xf86" 6468 PREFERRED_PROVIDER_virtual/libgl ?= "mesa" 6469 6470 For more 6471 information, see the ":ref:`dev-manual/new-recipe:using virtual providers`" 6472 section in the Yocto Project Development Tasks Manual. 6473 6474 .. note:: 6475 6476 If you use a ``virtual/\*`` item with :term:`PREFERRED_PROVIDER`, then any 6477 recipe that :term:`PROVIDES` that item but is not selected (defined) 6478 by :term:`PREFERRED_PROVIDER` is prevented from building, which is usually 6479 desirable since this mechanism is designed to select between mutually 6480 exclusive alternative providers. 6481 6482 :term:`PREFERRED_PROVIDERS` 6483 See :term:`bitbake:PREFERRED_PROVIDERS` in the BitBake manual. 6484 6485 :term:`PREFERRED_VERSION` 6486 If there are multiple versions of a recipe available, this variable 6487 determines which version should be given preference. You must always 6488 suffix the variable with the :term:`PN` you want to select (`python` in 6489 the first example below), and you should specify the :term:`PV` 6490 accordingly (`3.4.0` in the example). 6491 6492 The :term:`PREFERRED_VERSION` variable supports limited wildcard use 6493 through the "``%``" character. You can use the character to match any 6494 number of characters, which can be useful when specifying versions 6495 that contain long revision numbers that potentially change. Here are 6496 two examples:: 6497 6498 PREFERRED_VERSION_python = "3.4.0" 6499 PREFERRED_VERSION_linux-yocto = "5.0%" 6500 6501 .. note:: 6502 6503 The use of the "%" character is limited in that it only works at the end of the 6504 string. You cannot use the wildcard character in any other 6505 location of the string. 6506 6507 The specified version is matched against :term:`PV`, which 6508 does not necessarily match the version part of the recipe's filename. 6509 For example, consider two recipes ``foo_1.2.bb`` and ``foo_git.bb`` 6510 where ``foo_git.bb`` contains the following assignment:: 6511 6512 PV = "1.1+git${SRCPV}" 6513 6514 In this case, the correct way to select 6515 ``foo_git.bb`` is by using an assignment such as the following:: 6516 6517 PREFERRED_VERSION_foo = "1.1+git%" 6518 6519 Compare that previous example 6520 against the following incorrect example, which does not work:: 6521 6522 PREFERRED_VERSION_foo = "git" 6523 6524 Sometimes the :term:`PREFERRED_VERSION` variable can be set by 6525 configuration files in a way that is hard to change. You can use 6526 :term:`OVERRIDES` to set a machine-specific 6527 override. Here is an example:: 6528 6529 PREFERRED_VERSION_linux-yocto:qemux86 = "5.0%" 6530 6531 Although not recommended, worst case, you can also use the 6532 "forcevariable" override, which is the strongest override possible. 6533 Here is an example:: 6534 6535 PREFERRED_VERSION_linux-yocto:forcevariable = "5.0%" 6536 6537 .. note:: 6538 6539 The ``:forcevariable`` override is not handled specially. This override 6540 only works because the default value of :term:`OVERRIDES` includes "forcevariable". 6541 6542 If a recipe with the specified version is not available, a warning 6543 message will be shown. See :term:`REQUIRED_VERSION` if you want this 6544 to be an error instead. 6545 6546 :term:`PREMIRRORS` 6547 Specifies additional paths from which the OpenEmbedded build system 6548 gets source code. When the build system searches for source code, it 6549 first tries the local download directory. If that location fails, the 6550 build system tries locations defined by :term:`PREMIRRORS`, the upstream 6551 source, and then locations specified by 6552 :term:`MIRRORS` in that order. 6553 6554 Assuming your distribution (:term:`DISTRO`) is "poky", 6555 the default value for :term:`PREMIRRORS` is defined in the 6556 ``conf/distro/poky.conf`` file in the ``meta-poky`` Git repository. 6557 6558 Typically, you could add a specific server for the build system to 6559 attempt before any others by adding something like the following to 6560 the ``local.conf`` configuration file in the 6561 :term:`Build Directory`:: 6562 6563 PREMIRRORS:prepend = "\ 6564 git://.*/.* &YOCTO_DL_URL;/mirror/sources/ \ 6565 ftp://.*/.* &YOCTO_DL_URL;/mirror/sources/ \ 6566 http://.*/.* &YOCTO_DL_URL;/mirror/sources/ \ 6567 https://.*/.* &YOCTO_DL_URL;/mirror/sources/" 6568 6569 These changes cause the 6570 build system to intercept Git, FTP, HTTP, and HTTPS requests and 6571 direct them to the ``http://`` sources mirror. You can use 6572 ``file://`` URLs to point to local directories or network shares as 6573 well. 6574 6575 :term:`PRIORITY` 6576 Indicates the importance of a package. 6577 6578 :term:`PRIORITY` is considered to be part of the distribution policy 6579 because the importance of any given recipe depends on the purpose for 6580 which the distribution is being produced. Thus, :term:`PRIORITY` is not 6581 normally set within recipes. 6582 6583 You can set :term:`PRIORITY` to "required", "standard", "extra", and 6584 "optional", which is the default. 6585 6586 :term:`PRIVATE_LIBS` 6587 Specifies libraries installed within a recipe that should be ignored 6588 by the OpenEmbedded build system's shared library resolver. This 6589 variable is typically used when software being built by a recipe has 6590 its own private versions of a library normally provided by another 6591 recipe. In this case, you would not want the package containing the 6592 private libraries to be set as a dependency on other unrelated 6593 packages that should instead depend on the package providing the 6594 standard version of the library. 6595 6596 Libraries specified in this variable should be specified by their 6597 file name. For example, from the Firefox recipe in meta-browser:: 6598 6599 PRIVATE_LIBS = "libmozjs.so \ 6600 libxpcom.so \ 6601 libnspr4.so \ 6602 libxul.so \ 6603 libmozalloc.so \ 6604 libplc4.so \ 6605 libplds4.so" 6606 6607 For more information, see the 6608 ":ref:`overview-manual/concepts:automatically added runtime dependencies`" 6609 section in the Yocto Project Overview and Concepts Manual. 6610 6611 :term:`PROVIDES` 6612 A list of aliases by which a particular recipe can be known. By 6613 default, a recipe's own :term:`PN` is implicitly already in its 6614 :term:`PROVIDES` list and therefore does not need to mention that it 6615 provides itself. If a recipe uses :term:`PROVIDES`, the additional 6616 aliases are synonyms for the recipe and can be useful for satisfying 6617 dependencies of other recipes during the build as specified by 6618 :term:`DEPENDS`. 6619 6620 Consider the following example :term:`PROVIDES` statement from the recipe 6621 file ``eudev_3.2.9.bb``:: 6622 6623 PROVIDES += "udev" 6624 6625 The :term:`PROVIDES` statement 6626 results in the "eudev" recipe also being available as simply "udev". 6627 6628 .. note:: 6629 6630 A recipe's own recipe name (:term:`PN`) is always implicitly prepended 6631 to :term:`PROVIDES`, so while using "+=" in the above example may not be 6632 strictly necessary it is recommended to avoid confusion. 6633 6634 In addition to providing recipes under alternate names, the 6635 :term:`PROVIDES` mechanism is also used to implement virtual targets. A 6636 virtual target is a name that corresponds to some particular 6637 functionality (e.g. a Linux kernel). Recipes that provide the 6638 functionality in question list the virtual target in :term:`PROVIDES`. 6639 Recipes that depend on the functionality in question can include the 6640 virtual target in :term:`DEPENDS` to leave the choice of provider open. 6641 6642 Conventionally, virtual targets have names on the form 6643 "virtual/function" (e.g. "virtual/kernel"). The slash is simply part 6644 of the name and has no syntactical significance. 6645 6646 The :term:`PREFERRED_PROVIDER` variable is 6647 used to select which particular recipe provides a virtual target. 6648 6649 .. note:: 6650 6651 A corresponding mechanism for virtual runtime dependencies 6652 (packages) exists. However, the mechanism does not depend on any 6653 special functionality beyond ordinary variable assignments. For 6654 example, ``VIRTUAL-RUNTIME_dev_manager`` refers to the package of 6655 the component that manages the ``/dev`` directory. 6656 6657 Setting the "preferred provider" for runtime dependencies is as 6658 simple as using the following assignment in a configuration file:: 6659 6660 VIRTUAL-RUNTIME_dev_manager = "udev" 6661 6662 6663 :term:`PRSERV_HOST` 6664 The network based :term:`PR` service host and port. 6665 6666 The ``conf/templates/default/local.conf.sample.extended`` configuration 6667 file in the :term:`Source Directory` shows how the :term:`PRSERV_HOST` 6668 variable is set:: 6669 6670 PRSERV_HOST = "localhost:0" 6671 6672 You must 6673 set the variable if you want to automatically start a local :ref:`PR 6674 service <dev-manual/packages:working with a pr service>`. You can 6675 set :term:`PRSERV_HOST` to other values to use a remote PR service. 6676 6677 6678 :term:`PSEUDO_IGNORE_PATHS` 6679 A comma-separated (without spaces) list of path prefixes that should be ignored 6680 by pseudo when monitoring and recording file operations, in order to avoid 6681 problems with files being written to outside of the pseudo context and 6682 reduce pseudo's overhead. A path is ignored if it matches any prefix in the list 6683 and can include partial directory (or file) names. 6684 6685 6686 :term:`PTEST_ENABLED` 6687 Specifies whether or not :ref:`Package 6688 Test <dev-manual/packages:testing packages with ptest>` (ptest) 6689 functionality is enabled when building a recipe. You should not set 6690 this variable directly. Enabling and disabling building Package Tests 6691 at build time should be done by adding "ptest" to (or removing it 6692 from) :term:`DISTRO_FEATURES`. 6693 6694 :term:`PV` 6695 The version of the recipe. The version is normally extracted from the 6696 recipe filename. For example, if the recipe is named 6697 ``expat_2.0.1.bb``, then the default value of :term:`PV` will be "2.0.1". 6698 :term:`PV` is generally not overridden within a recipe unless it is 6699 building an unstable (i.e. development) version from a source code 6700 repository (e.g. Git or Subversion). 6701 6702 :term:`PV` is the default value of the :term:`PKGV` variable. 6703 6704 :term:`PYPI_PACKAGE` 6705 When inheriting the :ref:`ref-classes-pypi` class, specifies the 6706 `PyPI <https://pypi.org/>`__ package name to be built. The default value 6707 is set based upon :term:`BPN` (stripping any "python-" or "python3-" 6708 prefix off if present), however for some packages it will need to be set 6709 explicitly if that will not match the package name (e.g. where the 6710 package name has a prefix, underscores, uppercase letters etc.) 6711 6712 :term:`PYTHON_ABI` 6713 When used by recipes that inherit the :ref:`ref-classes-setuptools3` 6714 class, denotes the Application Binary Interface (ABI) currently in use 6715 for Python. By default, the ABI is "m". You do not have to set this 6716 variable as the OpenEmbedded build system sets it for you. 6717 6718 The OpenEmbedded build system uses the ABI to construct directory 6719 names used when installing the Python headers and libraries in 6720 sysroot (e.g. ``.../python3.3m/...``). 6721 6722 :term:`PYTHON_PN` 6723 When used by recipes that inherit the :ref:`ref-classes-setuptools3` 6724 class, specifies the major Python version being built. For Python 3.x, 6725 :term:`PYTHON_PN` would be "python3". You do not have to set this 6726 variable as the OpenEmbedded build system automatically sets it for you. 6727 6728 The variable allows recipes to use common infrastructure such as the 6729 following:: 6730 6731 DEPENDS += "${PYTHON_PN}-native" 6732 6733 In the previous example, 6734 the version of the dependency is :term:`PYTHON_PN`. 6735 6736 :term:`QA_EMPTY_DIRS` 6737 Specifies a list of directories that are expected to be empty when 6738 packaging; if ``empty-dirs`` appears in :term:`ERROR_QA` or 6739 :term:`WARN_QA` these will be checked and an error or warning 6740 (respectively) will be produced. 6741 6742 The default :term:`QA_EMPTY_DIRS` value is set in 6743 :ref:`insane.bbclass <ref-classes-insane>`. 6744 6745 :term:`QA_EMPTY_DIRS_RECOMMENDATION` 6746 Specifies a recommendation for why a directory must be empty, 6747 which will be included in the error message if a specific directory 6748 is found to contain files. Must be overridden with the directory 6749 path to match on. 6750 6751 If no recommendation is specified for a directory, then the default 6752 "but it is expected to be empty" will be used. 6753 6754 An example message shows if files were present in '/dev':: 6755 6756 QA_EMPTY_DIRS_RECOMMENDATION:/dev = "but all devices must be created at runtime" 6757 6758 :term:`RANLIB` 6759 The minimal command and arguments to run ``ranlib``. 6760 6761 :term:`RCONFLICTS` 6762 The list of packages that conflict with packages. Note that packages 6763 will not be installed if conflicting packages are not first removed. 6764 6765 Like all package-controlling variables, you must always use them in 6766 conjunction with a package name override. Here is an example:: 6767 6768 RCONFLICTS:${PN} = "another_conflicting_package_name" 6769 6770 BitBake, which the OpenEmbedded build system uses, supports 6771 specifying versioned dependencies. Although the syntax varies 6772 depending on the packaging format, BitBake hides these differences 6773 from you. Here is the general syntax to specify versions with the 6774 :term:`RCONFLICTS` variable:: 6775 6776 RCONFLICTS:${PN} = "package (operator version)" 6777 6778 For ``operator``, you can specify the following: 6779 6780 - = 6781 - < 6782 - > 6783 - <= 6784 - >= 6785 6786 For example, the following sets up a dependency on version 1.2 or 6787 greater of the package ``foo``:: 6788 6789 RCONFLICTS:${PN} = "foo (>= 1.2)" 6790 6791 :term:`RDEPENDS` 6792 Lists runtime dependencies of a package. These dependencies are other 6793 packages that must be installed in order for the package to function 6794 correctly. As an example, the following assignment declares that the 6795 package ``foo`` needs the packages ``bar`` and ``baz`` to be 6796 installed:: 6797 6798 RDEPENDS:foo = "bar baz" 6799 6800 The most common types of package 6801 runtime dependencies are automatically detected and added. Therefore, 6802 most recipes do not need to set :term:`RDEPENDS`. For more information, 6803 see the 6804 ":ref:`overview-manual/concepts:automatically added runtime dependencies`" 6805 section in the Yocto Project Overview and Concepts Manual. 6806 6807 The practical effect of the above :term:`RDEPENDS` assignment is that 6808 ``bar`` and ``baz`` will be declared as dependencies inside the 6809 package ``foo`` when it is written out by one of the 6810 :ref:`do_package_write_* <ref-tasks-package_write_deb>` tasks. 6811 Exactly how this is done depends on which package format is used, 6812 which is determined by 6813 :term:`PACKAGE_CLASSES`. When the 6814 corresponding package manager installs the package, it will know to 6815 also install the packages on which it depends. 6816 6817 To ensure that the packages ``bar`` and ``baz`` get built, the 6818 previous :term:`RDEPENDS` assignment also causes a task dependency to be 6819 added. This dependency is from the recipe's 6820 :ref:`ref-tasks-build` (not to be confused with 6821 :ref:`ref-tasks-compile`) task to the 6822 :ref:`do_package_write_* <ref-tasks-package_write_deb>` task of the recipes that build ``bar`` and 6823 ``baz``. 6824 6825 The names of the packages you list within :term:`RDEPENDS` must be the 6826 names of other packages --- they cannot be recipe names. Although 6827 package names and recipe names usually match, the important point 6828 here is that you are providing package names within the :term:`RDEPENDS` 6829 variable. For an example of the default list of packages created from 6830 a recipe, see the :term:`PACKAGES` variable. 6831 6832 Because the :term:`RDEPENDS` variable applies to packages being built, 6833 you should always use the variable in a form with an attached package 6834 name (remember that a single recipe can build multiple packages). For 6835 example, suppose you are building a development package that depends 6836 on the ``perl`` package. In this case, you would use the following 6837 :term:`RDEPENDS` statement:: 6838 6839 RDEPENDS:${PN}-dev += "perl" 6840 6841 In the example, 6842 the development package depends on the ``perl`` package. Thus, the 6843 :term:`RDEPENDS` variable has the ``${PN}-dev`` package name as part of 6844 the variable. 6845 6846 .. note:: 6847 6848 ``RDEPENDS:${PN}-dev`` includes ``${``\ :term:`PN`\ ``}`` 6849 by default. This default is set in the BitBake configuration file 6850 (``meta/conf/bitbake.conf``). Be careful not to accidentally remove 6851 ``${PN}`` when modifying ``RDEPENDS:${PN}-dev``. Use the "+=" operator 6852 rather than the "=" operator. 6853 6854 The package names you use with :term:`RDEPENDS` must appear as they would 6855 in the :term:`PACKAGES` variable. The :term:`PKG` variable 6856 allows a different name to be used for the final package (e.g. the 6857 :ref:`ref-classes-debian` class uses this to rename 6858 packages), but this final package name cannot be used with 6859 :term:`RDEPENDS`, which makes sense as :term:`RDEPENDS` is meant to be 6860 independent of the package format used. 6861 6862 BitBake, which the OpenEmbedded build system uses, supports 6863 specifying versioned dependencies. Although the syntax varies 6864 depending on the packaging format, BitBake hides these differences 6865 from you. Here is the general syntax to specify versions with the 6866 :term:`RDEPENDS` variable:: 6867 6868 RDEPENDS:${PN} = "package (operator version)" 6869 6870 For ``operator``, you can specify the following: 6871 6872 - = 6873 - < 6874 - > 6875 - <= 6876 - >= 6877 6878 For version, provide the version number. 6879 6880 .. note:: 6881 6882 You can use :term:`EXTENDPKGV` to provide a full package version 6883 specification. 6884 6885 For example, the following sets up a dependency on version 1.2 or 6886 greater of the package ``foo``:: 6887 6888 RDEPENDS:${PN} = "foo (>= 1.2)" 6889 6890 For information on build-time dependencies, see the :term:`DEPENDS` 6891 variable. You can also see the 6892 ":ref:`bitbake-user-manual/bitbake-user-manual-metadata:tasks`" and 6893 ":ref:`bitbake-user-manual/bitbake-user-manual-execution:dependencies`" sections in the 6894 BitBake User Manual for additional information on tasks and dependencies. 6895 6896 :term:`RECIPE_NO_UPDATE_REASON` 6897 If a recipe should not be replaced by a more recent upstream version, 6898 putting the reason why in this variable in a recipe allows 6899 ``devtool check-upgrade-status`` command to display it, as explained 6900 in the ":ref:`ref-manual/devtool-reference:checking on the upgrade status of a recipe`" 6901 section. 6902 6903 :term:`REPODIR` 6904 See :term:`bitbake:REPODIR` in the BitBake manual. 6905 6906 :term:`REQUIRED_DISTRO_FEATURES` 6907 When inheriting the :ref:`ref-classes-features_check` 6908 class, this variable identifies distribution features that must exist 6909 in the current configuration in order for the OpenEmbedded build 6910 system to build the recipe. In other words, if the 6911 :term:`REQUIRED_DISTRO_FEATURES` variable lists a feature that does not 6912 appear in :term:`DISTRO_FEATURES` within the current configuration, then 6913 the recipe will be skipped, and if the build system attempts to build 6914 the recipe then an error will be triggered. 6915 6916 :term:`REQUIRED_VERSION` 6917 If there are multiple versions of a recipe available, this variable 6918 determines which version should be given preference. 6919 :term:`REQUIRED_VERSION` works in exactly the same manner as 6920 :term:`PREFERRED_VERSION`, except that if the specified version is not 6921 available then an error message is shown and the build fails 6922 immediately. 6923 6924 If both :term:`REQUIRED_VERSION` and :term:`PREFERRED_VERSION` are set 6925 for the same recipe, the :term:`REQUIRED_VERSION` value applies. 6926 6927 :term:`RM_WORK_EXCLUDE` 6928 With :ref:`ref-classes-rm-work` enabled, this variable 6929 specifies a list of recipes whose work directories should not be removed. 6930 See the ":ref:`ref-classes-rm-work`" section for more details. 6931 6932 :term:`ROOT_HOME` 6933 Defines the root home directory. By default, this directory is set as 6934 follows in the BitBake configuration file:: 6935 6936 ROOT_HOME ??= "/home/root" 6937 6938 .. note:: 6939 6940 This default value is likely used because some embedded solutions 6941 prefer to have a read-only root filesystem and prefer to keep 6942 writeable data in one place. 6943 6944 You can override the default by setting the variable in any layer or 6945 in the ``local.conf`` file. Because the default is set using a "weak" 6946 assignment (i.e. "??="), you can use either of the following forms to 6947 define your override:: 6948 6949 ROOT_HOME = "/root" 6950 ROOT_HOME ?= "/root" 6951 6952 These 6953 override examples use ``/root``, which is probably the most commonly 6954 used override. 6955 6956 :term:`ROOTFS` 6957 Indicates a filesystem image to include as the root filesystem. 6958 6959 The :term:`ROOTFS` variable is an optional variable used with the 6960 :ref:`ref-classes-image-live` class. 6961 6962 :term:`ROOTFS_POSTINSTALL_COMMAND` 6963 Specifies a list of functions to call after the OpenEmbedded build 6964 system has installed packages. You can specify functions separated by 6965 semicolons:: 6966 6967 ROOTFS_POSTINSTALL_COMMAND += "function; ... " 6968 6969 If you need to pass the root filesystem path to a command within a 6970 function, you can use ``${IMAGE_ROOTFS}``, which points to the 6971 directory that becomes the root filesystem image. See the 6972 :term:`IMAGE_ROOTFS` variable for more 6973 information. 6974 6975 :term:`ROOTFS_POSTPROCESS_COMMAND` 6976 Specifies a list of functions to call once the OpenEmbedded build 6977 system has created the root filesystem. You can specify functions 6978 separated by semicolons:: 6979 6980 ROOTFS_POSTPROCESS_COMMAND += "function; ... " 6981 6982 If you need to pass the root filesystem path to a command within a 6983 function, you can use ``${IMAGE_ROOTFS}``, which points to the 6984 directory that becomes the root filesystem image. See the 6985 :term:`IMAGE_ROOTFS` variable for more 6986 information. 6987 6988 :term:`ROOTFS_POSTUNINSTALL_COMMAND` 6989 Specifies a list of functions to call after the OpenEmbedded build 6990 system has removed unnecessary packages. When runtime package 6991 management is disabled in the image, several packages are removed 6992 including ``base-passwd``, ``shadow``, and ``update-alternatives``. 6993 You can specify functions separated by semicolons:: 6994 6995 ROOTFS_POSTUNINSTALL_COMMAND += "function; ... " 6996 6997 If you need to pass the root filesystem path to a command within a 6998 function, you can use ``${IMAGE_ROOTFS}``, which points to the 6999 directory that becomes the root filesystem image. See the 7000 :term:`IMAGE_ROOTFS` variable for more 7001 information. 7002 7003 :term:`ROOTFS_PREPROCESS_COMMAND` 7004 Specifies a list of functions to call before the OpenEmbedded build 7005 system has created the root filesystem. You can specify functions 7006 separated by semicolons:: 7007 7008 ROOTFS_PREPROCESS_COMMAND += "function; ... " 7009 7010 If you need to pass the root filesystem path to a command within a 7011 function, you can use ``${IMAGE_ROOTFS}``, which points to the 7012 directory that becomes the root filesystem image. See the 7013 :term:`IMAGE_ROOTFS` variable for more 7014 information. 7015 7016 :term:`RPROVIDES` 7017 A list of package name aliases that a package also provides. These 7018 aliases are useful for satisfying runtime dependencies of other 7019 packages both during the build and on the target (as specified by 7020 :term:`RDEPENDS`). 7021 7022 .. note:: 7023 7024 A package's own name is implicitly already in its :term:`RPROVIDES` list. 7025 7026 As with all package-controlling variables, you must always use the 7027 variable in conjunction with a package name override. Here is an 7028 example:: 7029 7030 RPROVIDES:${PN} = "widget-abi-2" 7031 7032 :term:`RRECOMMENDS` 7033 A list of packages that extends the usability of a package being 7034 built. The package being built does not depend on this list of 7035 packages in order to successfully build, but rather uses them for 7036 extended usability. To specify runtime dependencies for packages, see 7037 the :term:`RDEPENDS` variable. 7038 7039 The package manager will automatically install the :term:`RRECOMMENDS` 7040 list of packages when installing the built package. However, you can 7041 prevent listed packages from being installed by using the 7042 :term:`BAD_RECOMMENDATIONS`, 7043 :term:`NO_RECOMMENDATIONS`, and 7044 :term:`PACKAGE_EXCLUDE` variables. 7045 7046 Packages specified in :term:`RRECOMMENDS` need not actually be produced. 7047 However, there must be a recipe providing each package, either 7048 through the :term:`PACKAGES` or 7049 :term:`PACKAGES_DYNAMIC` variables or the 7050 :term:`RPROVIDES` variable, or an error will occur 7051 during the build. If such a recipe does exist and the package is not 7052 produced, the build continues without error. 7053 7054 Because the :term:`RRECOMMENDS` variable applies to packages being built, 7055 you should always attach an override to the variable to specify the 7056 particular package whose usability is being extended. For example, 7057 suppose you are building a development package that is extended to 7058 support wireless functionality. In this case, you would use the 7059 following:: 7060 7061 RRECOMMENDS:${PN}-dev += "wireless_package_name" 7062 7063 In the 7064 example, the package name (``${PN}-dev``) must appear as it would in 7065 the :term:`PACKAGES` namespace before any renaming of the output package 7066 by classes such as :ref:`ref-classes-debian`. 7067 7068 BitBake, which the OpenEmbedded build system uses, supports 7069 specifying versioned recommends. Although the syntax varies depending 7070 on the packaging format, BitBake hides these differences from you. 7071 Here is the general syntax to specify versions with the 7072 :term:`RRECOMMENDS` variable:: 7073 7074 RRECOMMENDS:${PN} = "package (operator version)" 7075 7076 For ``operator``, you can specify the following: 7077 7078 - = 7079 - < 7080 - > 7081 - <= 7082 - >= 7083 7084 For example, the following sets up a recommend on version 1.2 or 7085 greater of the package ``foo``:: 7086 7087 RRECOMMENDS:${PN} = "foo (>= 1.2)" 7088 7089 :term:`RREPLACES` 7090 A list of packages replaced by a package. The package manager uses 7091 this variable to determine which package should be installed to 7092 replace other package(s) during an upgrade. In order to also have the 7093 other package(s) removed at the same time, you must add the name of 7094 the other package to the :term:`RCONFLICTS` variable. 7095 7096 As with all package-controlling variables, you must use this variable 7097 in conjunction with a package name override. Here is an example:: 7098 7099 RREPLACES:${PN} = "other_package_being_replaced" 7100 7101 BitBake, which the OpenEmbedded build system uses, supports 7102 specifying versioned replacements. Although the syntax varies 7103 depending on the packaging format, BitBake hides these differences 7104 from you. Here is the general syntax to specify versions with the 7105 :term:`RREPLACES` variable:: 7106 7107 RREPLACES:${PN} = "package (operator version)" 7108 7109 For ``operator``, you can specify the following: 7110 7111 - = 7112 - < 7113 - > 7114 - <= 7115 - >= 7116 7117 For example, the following sets up a replacement using version 1.2 7118 or greater of the package ``foo``:: 7119 7120 RREPLACES:${PN} = "foo (>= 1.2)" 7121 7122 :term:`RSUGGESTS` 7123 A list of additional packages that you can suggest for installation 7124 by the package manager at the time a package is installed. Not all 7125 package managers support this functionality. 7126 7127 As with all package-controlling variables, you must always use this 7128 variable in conjunction with a package name override. Here is an 7129 example:: 7130 7131 RSUGGESTS:${PN} = "useful_package another_package" 7132 7133 :term:`RUST_CHANNEL` 7134 Specifies which version of Rust to build - "stable", "beta" or "nightly". 7135 The default value is "stable". Set this at your own risk, as values other 7136 than "stable" are not guaranteed to work at a given time. 7137 7138 :term:`S` 7139 The location in the :term:`Build Directory` where 7140 unpacked recipe source code resides. By default, this directory is 7141 ``${``\ :term:`WORKDIR`\ ``}/${``\ :term:`BPN`\ ``}-${``\ :term:`PV`\ ``}``, 7142 where ``${BPN}`` is the base recipe name and ``${PV}`` is the recipe 7143 version. If the source tarball extracts the code to a directory named 7144 anything other than ``${BPN}-${PV}``, or if the source code is 7145 fetched from an SCM such as Git or Subversion, then you must set 7146 :term:`S` in the recipe so that the OpenEmbedded build system knows where 7147 to find the unpacked source. 7148 7149 As an example, assume a :term:`Source Directory` 7150 top-level folder named ``poky`` and a default :term:`Build Directory` at 7151 ``poky/build``. In this case, the work directory the build system 7152 uses to keep the unpacked recipe for ``db`` is the following:: 7153 7154 poky/build/tmp/work/qemux86-poky-linux/db/5.1.19-r3/db-5.1.19 7155 7156 The unpacked source code resides in the ``db-5.1.19`` folder. 7157 7158 This next example assumes a Git repository. By default, Git 7159 repositories are cloned to ``${WORKDIR}/git`` during 7160 :ref:`ref-tasks-fetch`. Since this path is different 7161 from the default value of :term:`S`, you must set it specifically so the 7162 source can be located:: 7163 7164 SRC_URI = "git://path/to/repo.git;branch=main" 7165 S = "${WORKDIR}/git" 7166 7167 :term:`SANITY_REQUIRED_UTILITIES` 7168 Specifies a list of command-line utilities that should be checked for 7169 during the initial sanity checking process when running BitBake. If 7170 any of the utilities are not installed on the build host, then 7171 BitBake immediately exits with an error. 7172 7173 :term:`SANITY_TESTED_DISTROS` 7174 A list of the host distribution identifiers that the build system has 7175 been tested against. Identifiers consist of the host distributor ID 7176 followed by the release, as reported by the ``lsb_release`` tool or 7177 as read from ``/etc/lsb-release``. Separate the list items with 7178 explicit newline characters (``\n``). If :term:`SANITY_TESTED_DISTROS` is 7179 not empty and the current value of 7180 :term:`NATIVELSBSTRING` does not appear in the 7181 list, then the build system reports a warning that indicates the 7182 current host distribution has not been tested as a build host. 7183 7184 :term:`SDK_ARCH` 7185 The target architecture for the SDK. Typically, you do not directly 7186 set this variable. Instead, use :term:`SDKMACHINE`. 7187 7188 :term:`SDK_ARCHIVE_TYPE` 7189 Specifies the type of archive to create for the SDK. Valid values: 7190 7191 - ``tar.xz`` (default) 7192 - ``zip`` 7193 7194 Only one archive type can be specified. 7195 7196 :term:`SDK_BUILDINFO_FILE` 7197 When using the :ref:`ref-classes-image-buildinfo` class, 7198 specifies the file in the SDK to write the build information into. The 7199 default value is "``/buildinfo``". 7200 7201 :term:`SDK_CUSTOM_TEMPLATECONF` 7202 When building the extensible SDK, if :term:`SDK_CUSTOM_TEMPLATECONF` is set to 7203 "1" and a ``conf/templateconf.cfg`` file exists in the :term:`Build Directory` 7204 (:term:`TOPDIR`) then this will be copied into the SDK. 7205 7206 :term:`SDK_DEPLOY` 7207 The directory set up and used by the 7208 :ref:`populate_sdk_base <ref-classes-populate-sdk>` class to which the 7209 SDK is deployed. The :ref:`populate_sdk_base <ref-classes-populate-sdk>` 7210 class defines :term:`SDK_DEPLOY` as follows:: 7211 7212 SDK_DEPLOY = "${TMPDIR}/deploy/sdk" 7213 7214 :term:`SDK_DIR` 7215 The parent directory used by the OpenEmbedded build system when 7216 creating SDK output. The 7217 :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` class defines 7218 the variable as follows:: 7219 7220 SDK_DIR = "${WORKDIR}/sdk" 7221 7222 .. note:: 7223 7224 The :term:`SDK_DIR` directory is a temporary directory as it is part of 7225 :term:`WORKDIR`. The final output directory is :term:`SDK_DEPLOY`. 7226 7227 :term:`SDK_EXT_TYPE` 7228 Controls whether or not shared state artifacts are copied into the 7229 extensible SDK. The default value of "full" copies all of the 7230 required shared state artifacts into the extensible SDK. The value 7231 "minimal" leaves these artifacts out of the SDK. 7232 7233 .. note:: 7234 7235 If you set the variable to "minimal", you need to ensure 7236 :term:`SSTATE_MIRRORS` is set in the SDK's configuration to enable the 7237 artifacts to be fetched as needed. 7238 7239 :term:`SDK_HOST_MANIFEST` 7240 The manifest file for the host part of the SDK. This file lists all 7241 the installed packages that make up the host part of the SDK. The 7242 file contains package information on a line-per-package basis as 7243 follows:: 7244 7245 packagename packagearch version 7246 7247 The :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` class 7248 defines the manifest file as follows:: 7249 7250 SDK_HOST_MANIFEST = "${SDK_DEPLOY}/${TOOLCHAIN_OUTPUTNAME}.host.manifest" 7251 7252 The location is derived using the :term:`SDK_DEPLOY` and 7253 :term:`TOOLCHAIN_OUTPUTNAME` variables. 7254 7255 :term:`SDK_INCLUDE_PKGDATA` 7256 When set to "1", specifies to include the packagedata for all recipes 7257 in the "world" target in the extensible SDK. Including this data 7258 allows the ``devtool search`` command to find these recipes in search 7259 results, as well as allows the ``devtool add`` command to map 7260 dependencies more effectively. 7261 7262 .. note:: 7263 7264 Enabling the :term:`SDK_INCLUDE_PKGDATA` 7265 variable significantly increases build time because all of world 7266 needs to be built. Enabling the variable also slightly increases 7267 the size of the extensible SDK. 7268 7269 :term:`SDK_INCLUDE_TOOLCHAIN` 7270 When set to "1", specifies to include the toolchain in the extensible 7271 SDK. Including the toolchain is useful particularly when 7272 :term:`SDK_EXT_TYPE` is set to "minimal" to keep 7273 the SDK reasonably small but you still want to provide a usable 7274 toolchain. For example, suppose you want to use the toolchain from an 7275 IDE or from other tools and you do not want to perform additional 7276 steps to install the toolchain. 7277 7278 The :term:`SDK_INCLUDE_TOOLCHAIN` variable defaults to "0" if 7279 :term:`SDK_EXT_TYPE` is set to "minimal", and defaults to "1" if 7280 :term:`SDK_EXT_TYPE` is set to "full". 7281 7282 :term:`SDK_NAME` 7283 The base name for SDK output files. The name is derived from the 7284 :term:`DISTRO`, :term:`TCLIBC`, 7285 :term:`SDK_ARCH`, 7286 :term:`IMAGE_BASENAME`, and 7287 :term:`TUNE_PKGARCH` variables:: 7288 7289 SDK_NAME = "${DISTRO}-${TCLIBC}-${SDK_ARCH}-${IMAGE_BASENAME}-${TUNE_PKGARCH}" 7290 7291 :term:`SDK_OS` 7292 Specifies the operating system for which the SDK will be built. The 7293 default value is the value of :term:`BUILD_OS`. 7294 7295 :term:`SDK_OUTPUT` 7296 The location used by the OpenEmbedded build system when creating SDK 7297 output. The :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` 7298 class defines the variable as follows:: 7299 7300 SDK_DIR = "${WORKDIR}/sdk" 7301 SDK_OUTPUT = "${SDK_DIR}/image" 7302 SDK_DEPLOY = "${DEPLOY_DIR}/sdk" 7303 7304 .. note:: 7305 7306 The :term:`SDK_OUTPUT` directory is a temporary directory as it is part of 7307 :term:`WORKDIR` by way of :term:`SDK_DIR`. The final output directory is 7308 :term:`SDK_DEPLOY`. 7309 7310 :term:`SDK_PACKAGE_ARCHS` 7311 Specifies a list of architectures compatible with the SDK machine. 7312 This variable is set automatically and should not normally be 7313 hand-edited. Entries are separated using spaces and listed in order 7314 of priority. The default value for :term:`SDK_PACKAGE_ARCHS` is "all any 7315 noarch ${SDK_ARCH}-${SDKPKGSUFFIX}". 7316 7317 :term:`SDK_POSTPROCESS_COMMAND` 7318 Specifies a list of functions to call once the OpenEmbedded build 7319 system creates the SDK. You can specify functions separated by 7320 semicolons: SDK_POSTPROCESS_COMMAND += "function; ... " 7321 7322 If you need to pass an SDK path to a command within a function, you 7323 can use ``${SDK_DIR}``, which points to the parent directory used by 7324 the OpenEmbedded build system when creating SDK output. See the 7325 :term:`SDK_DIR` variable for more information. 7326 7327 :term:`SDK_PREFIX` 7328 The toolchain binary prefix used for 7329 :ref:`ref-classes-nativesdk` recipes. The 7330 OpenEmbedded build system uses the :term:`SDK_PREFIX` value to set the 7331 :term:`TARGET_PREFIX` when building 7332 ``nativesdk`` recipes. The default value is "${SDK_SYS}-". 7333 7334 :term:`SDK_RECRDEP_TASKS` 7335 A list of shared state tasks added to the extensible SDK. By default, 7336 the following tasks are added: 7337 7338 - :ref:`ref-tasks-populate_lic` 7339 - :ref:`ref-tasks-package_qa` 7340 - :ref:`ref-tasks-populate_sysroot` 7341 - :ref:`ref-tasks-deploy` 7342 7343 Despite the default value of "" for the 7344 :term:`SDK_RECRDEP_TASKS` variable, the above four tasks are always added 7345 to the SDK. To specify tasks beyond these four, you need to use the 7346 :term:`SDK_RECRDEP_TASKS` variable (e.g. you are defining additional 7347 tasks that are needed in order to build 7348 :term:`SDK_TARGETS`). 7349 7350 :term:`SDK_SYS` 7351 Specifies the system, including the architecture and the operating 7352 system, for which the SDK will be built. 7353 7354 The OpenEmbedded build system automatically sets this variable based 7355 on :term:`SDK_ARCH`, 7356 :term:`SDK_VENDOR`, and 7357 :term:`SDK_OS`. You do not need to set the :term:`SDK_SYS` 7358 variable yourself. 7359 7360 :term:`SDK_TARGET_MANIFEST` 7361 The manifest file for the target part of the SDK. This file lists all 7362 the installed packages that make up the target part of the SDK. The 7363 file contains package information on a line-per-package basis as 7364 follows:: 7365 7366 packagename packagearch version 7367 7368 The :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` class 7369 defines the manifest file as follows:: 7370 7371 SDK_TARGET_MANIFEST = "${SDK_DEPLOY}/${TOOLCHAIN_OUTPUTNAME}.target.manifest" 7372 7373 The location is derived using the :term:`SDK_DEPLOY` and 7374 :term:`TOOLCHAIN_OUTPUTNAME` variables. 7375 7376 :term:`SDK_TARGETS` 7377 A list of targets to install from shared state as part of the 7378 standard or extensible SDK installation. The default value is "${PN}" 7379 (i.e. the image from which the SDK is built). 7380 7381 The :term:`SDK_TARGETS` variable is an internal variable and typically 7382 would not be changed. 7383 7384 :term:`SDK_TITLE` 7385 The title to be printed when running the SDK installer. By default, 7386 this title is based on the :term:`DISTRO_NAME` or 7387 :term:`DISTRO` variable and is set in the 7388 :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` class as 7389 follows:: 7390 7391 SDK_TITLE ??= "${@d.getVar('DISTRO_NAME') or d.getVar('DISTRO')} SDK" 7392 7393 For the default distribution "poky", 7394 :term:`SDK_TITLE` is set to "Poky (Yocto Project Reference Distro)". 7395 7396 For information on how to change this default title, see the 7397 ":ref:`sdk-manual/appendix-customizing:changing the extensible sdk installer title`" 7398 section in the Yocto Project Application Development and the 7399 Extensible Software Development Kit (eSDK) manual. 7400 7401 :term:`SDK_TOOLCHAIN_LANGS` 7402 Specifies programming languages to support in the SDK, as a 7403 space-separated list. Currently supported items are ``rust`` and ``go``. 7404 7405 :term:`SDK_UPDATE_URL` 7406 An optional URL for an update server for the extensible SDK. If set, 7407 the value is used as the default update server when running 7408 ``devtool sdk-update`` within the extensible SDK. 7409 7410 :term:`SDK_VENDOR` 7411 Specifies the name of the SDK vendor. 7412 7413 :term:`SDK_VERSION` 7414 Specifies the version of the SDK. The Poky distribution configuration file 7415 (``/meta-poky/conf/distro/poky.conf``) sets the default 7416 :term:`SDK_VERSION` as follows:: 7417 7418 SDK_VERSION = "${@d.getVar('DISTRO_VERSION').replace('snapshot-${METADATA_REVISION}', 'snapshot')}" 7419 7420 For additional information, see the 7421 :term:`DISTRO_VERSION` and 7422 :term:`METADATA_REVISION` variables. 7423 7424 :term:`SDK_ZIP_OPTIONS` 7425 Specifies extra options to pass to the ``zip`` command when zipping the SDK 7426 (i.e. when :term:`SDK_ARCHIVE_TYPE` is set to "zip"). The default value is 7427 "-y". 7428 7429 :term:`SDKEXTPATH` 7430 The default installation directory for the Extensible SDK. By 7431 default, this directory is based on the :term:`DISTRO` 7432 variable and is set in the 7433 :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` class as 7434 follows:: 7435 7436 SDKEXTPATH ??= "~/${@d.getVar('DISTRO')}_sdk" 7437 7438 For the 7439 default distribution "poky", the :term:`SDKEXTPATH` is set to "poky_sdk". 7440 7441 For information on how to change this default directory, see the 7442 ":ref:`sdk-manual/appendix-customizing:changing the default sdk installation directory`" 7443 section in the Yocto Project Application Development and the 7444 Extensible Software Development Kit (eSDK) manual. 7445 7446 :term:`SDKIMAGE_FEATURES` 7447 Equivalent to :term:`IMAGE_FEATURES`. However, this variable applies to 7448 the SDK generated from an image using the following command:: 7449 7450 $ bitbake -c populate_sdk imagename 7451 7452 :term:`SDKMACHINE` 7453 The machine for which the SDK is built. In other words, the SDK is built 7454 such that it runs on the target you specify with the :term:`SDKMACHINE` 7455 value. The value points to a corresponding ``.conf`` file under 7456 ``conf/machine-sdk/`` in the enabled layers, for example ``aarch64``, 7457 ``i586``, ``i686``, ``ppc64``, ``ppc64le``, and ``x86_64`` are 7458 :oe_git:`available in OpenEmbedded-Core </openembedded-core/tree/meta/conf/machine-sdk>`. 7459 7460 The variable defaults to :term:`BUILD_ARCH` so that SDKs are built for the 7461 architecture of the build machine. 7462 7463 .. note:: 7464 7465 You cannot set the :term:`SDKMACHINE` 7466 variable in your distribution configuration file. If you do, the 7467 configuration will not take effect. 7468 7469 :term:`SDKPATH` 7470 Defines the path offered to the user for installation of the SDK that 7471 is generated by the OpenEmbedded build system. The path appears as 7472 the default location for installing the SDK when you run the SDK's 7473 installation script. You can override the offered path when you run 7474 the script. 7475 7476 :term:`SDKTARGETSYSROOT` 7477 The full path to the sysroot used for cross-compilation within an SDK 7478 as it will be when installed into the default 7479 :term:`SDKPATH`. 7480 7481 :term:`SECTION` 7482 The section in which packages should be categorized. Package 7483 management utilities can make use of this variable. 7484 7485 :term:`SELECTED_OPTIMIZATION` 7486 Specifies the optimization flags passed to the C compiler when 7487 building for the target. The flags are passed through the default 7488 value of the :term:`TARGET_CFLAGS` variable. 7489 7490 The :term:`SELECTED_OPTIMIZATION` variable takes the value of 7491 :term:`FULL_OPTIMIZATION` unless :term:`DEBUG_BUILD` = "1", in which 7492 case the value of :term:`DEBUG_OPTIMIZATION` is used. 7493 7494 :term:`SERIAL_CONSOLES` 7495 Defines a serial console (TTY) to enable using 7496 :wikipedia:`getty <Getty_(Unix)>`. Provide a value that specifies the 7497 baud rate followed by the TTY device name separated by a semicolon. 7498 Use spaces to separate multiple devices:: 7499 7500 SERIAL_CONSOLES = "115200;ttyS0 115200;ttyS1" 7501 7502 :term:`SERIAL_CONSOLES_CHECK` 7503 Specifies serial consoles, which must be listed in 7504 :term:`SERIAL_CONSOLES`, to check against 7505 ``/proc/console`` before enabling them using getty. This variable 7506 allows aliasing in the format: <device>:<alias>. If a device was 7507 listed as "sclp_line0" in ``/dev/`` and "ttyS0" was listed in 7508 ``/proc/console``, you would do the following:: 7509 7510 SERIAL_CONSOLES_CHECK = "slcp_line0:ttyS0" 7511 7512 This variable is currently only supported with SysVinit (i.e. not 7513 with systemd). Note that :term:`SERIAL_CONSOLES_CHECK` also requires 7514 ``/etc/inittab`` to be writable when used with SysVinit. This makes it 7515 incompatible with customizations such as the following:: 7516 7517 EXTRA_IMAGE_FEATURES += "read-only-rootfs" 7518 7519 :term:`SETUPTOOLS_BUILD_ARGS` 7520 When used by recipes that inherit the :ref:`ref-classes-setuptools3` 7521 class, this variable can be used to specify additional arguments to be 7522 passed to ``setup.py build`` in the ``setuptools3_do_compile()`` task. 7523 7524 :term:`SETUPTOOLS_INSTALL_ARGS` 7525 When used by recipes that inherit the :ref:`ref-classes-setuptools3` 7526 class, this variable can be used to specify additional arguments to be 7527 passed to ``setup.py install`` in the ``setuptools3_do_install()`` task. 7528 7529 :term:`SETUPTOOLS_SETUP_PATH` 7530 When used by recipes that inherit the :ref:`ref-classes-setuptools3` 7531 class, this variable should be used to specify the directory in which 7532 the ``setup.py`` file is located if it is not at the root of the source 7533 tree (as specified by :term:`S`). For example, in a recipe where the 7534 sources are fetched from a Git repository and ``setup.py`` is in a 7535 ``python/pythonmodule`` subdirectory, you would have this:: 7536 7537 S = "${WORKDIR}/git" 7538 SETUPTOOLS_SETUP_PATH = "${S}/python/pythonmodule" 7539 7540 :term:`SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS` 7541 A list of recipe dependencies that should not be used to determine 7542 signatures of tasks from one recipe when they depend on tasks from 7543 another recipe. For example:: 7544 7545 SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS += "intone->mplayer2" 7546 7547 In the previous example, ``intone`` depends on ``mplayer2``. 7548 7549 You can use the special token ``"*"`` on the left-hand side of the 7550 dependency to match all recipes except the one on the right-hand 7551 side. Here is an example:: 7552 7553 SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS += "*->quilt-native" 7554 7555 In the previous example, all recipes except ``quilt-native`` ignore 7556 task signatures from the ``quilt-native`` recipe when determining 7557 their task signatures. 7558 7559 Use of this variable is one mechanism to remove dependencies that 7560 affect task signatures and thus force rebuilds when a recipe changes. 7561 7562 .. note:: 7563 7564 If you add an inappropriate dependency for a recipe relationship, 7565 the software might break during runtime if the interface of the 7566 second recipe was changed after the first recipe had been built. 7567 7568 :term:`SIGGEN_EXCLUDERECIPES_ABISAFE` 7569 A list of recipes that are completely stable and will never change. 7570 The ABI for the recipes in the list are presented by output from the 7571 tasks run to build the recipe. Use of this variable is one way to 7572 remove dependencies from one recipe on another that affect task 7573 signatures and thus force rebuilds when the recipe changes. 7574 7575 .. note:: 7576 7577 If you add an inappropriate variable to this list, the software 7578 might break at runtime if the interface of the recipe was changed 7579 after the other had been built. 7580 7581 :term:`SITEINFO_BITS` 7582 Specifies the number of bits for the target system CPU. The value 7583 should be either "32" or "64". 7584 7585 :term:`SITEINFO_ENDIANNESS` 7586 Specifies the endian byte order of the target system. The value 7587 should be either "le" for little-endian or "be" for big-endian. 7588 7589 :term:`SKIP_FILEDEPS` 7590 Enables removal of all files from the "Provides" section of an RPM 7591 package. Removal of these files is required for packages containing 7592 prebuilt binaries and libraries such as ``libstdc++`` and ``glibc``. 7593 7594 To enable file removal, set the variable to "1" in your 7595 ``conf/local.conf`` configuration file in your: 7596 :term:`Build Directory`:: 7597 7598 SKIP_FILEDEPS = "1" 7599 7600 :term:`SKIP_RECIPE` 7601 Used to prevent the OpenEmbedded build system from building a given 7602 recipe. Specify the :term:`PN` value as a variable flag (``varflag``) 7603 and provide a reason, which will be reported when attempting to 7604 build the recipe. 7605 7606 To prevent a recipe from being built, use the :term:`SKIP_RECIPE` 7607 variable in your ``local.conf`` file or distribution configuration. 7608 Here is an example which prevents ``myrecipe`` from being built:: 7609 7610 SKIP_RECIPE[myrecipe] = "Not supported by our organization." 7611 7612 :term:`SOC_FAMILY` 7613 A colon-separated list grouping together machines based upon the same 7614 family of SoC (System On Chip). You typically set this variable in a 7615 common ``.inc`` file that you include in the configuration files of all 7616 the machines. 7617 7618 .. note:: 7619 7620 You must include ``conf/machine/include/soc-family.inc`` for this 7621 variable to appear in :term:`MACHINEOVERRIDES`. 7622 7623 :term:`SOLIBS` 7624 Defines the suffix for shared libraries used on the target platform. 7625 By default, this suffix is ".so.*" for all Linux-based systems and is 7626 defined in the ``meta/conf/bitbake.conf`` configuration file. 7627 7628 You will see this variable referenced in the default values of 7629 ``FILES:${PN}``. 7630 7631 :term:`SOLIBSDEV` 7632 Defines the suffix for the development symbolic link (symlink) for 7633 shared libraries on the target platform. By default, this suffix is 7634 ".so" for Linux-based systems and is defined in the 7635 ``meta/conf/bitbake.conf`` configuration file. 7636 7637 You will see this variable referenced in the default values of 7638 ``FILES:${PN}-dev``. 7639 7640 :term:`SOURCE_DATE_EPOCH` 7641 This defines a date expressed in number of seconds since 7642 the UNIX EPOCH (01 Jan 1970 00:00:00 UTC), which is used by 7643 multiple build systems to force a timestamp in built binaries. 7644 Many upstream projects already support this variable. 7645 7646 You will find more details in the `official specifications 7647 <https://reproducible-builds.org/specs/source-date-epoch/>`__. 7648 7649 A value for each recipe is computed from the sources by 7650 :oe_git:`meta/lib/oe/reproducible.py </openembedded-core/tree/meta/lib/oe/reproducible.py>`. 7651 7652 If a recipe wishes to override the default behavior, it should set its 7653 own :term:`SOURCE_DATE_EPOCH` value:: 7654 7655 SOURCE_DATE_EPOCH = "1613559011" 7656 7657 :term:`SOURCE_MIRROR_FETCH` 7658 When you are fetching files to create a mirror of sources (i.e. 7659 creating a source mirror), setting :term:`SOURCE_MIRROR_FETCH` to "1" in 7660 your ``local.conf`` configuration file ensures the source for all 7661 recipes are fetched regardless of whether or not a recipe is 7662 compatible with the configuration. A recipe is considered 7663 incompatible with the currently configured machine when either or 7664 both the :term:`COMPATIBLE_MACHINE` 7665 variable and :term:`COMPATIBLE_HOST` variables 7666 specify compatibility with a machine other than that of the current 7667 machine or host. 7668 7669 .. note:: 7670 7671 Do not set the :term:`SOURCE_MIRROR_FETCH` 7672 variable unless you are creating a source mirror. In other words, 7673 do not set the variable during a normal build. 7674 7675 :term:`SOURCE_MIRROR_URL` 7676 Defines your own :term:`PREMIRRORS` from which to 7677 first fetch source before attempting to fetch from the upstream 7678 specified in :term:`SRC_URI`. 7679 7680 To use this variable, you must globally inherit the 7681 :ref:`ref-classes-own-mirrors` class and then provide 7682 the URL to your mirrors. Here is the general syntax:: 7683 7684 INHERIT += "own-mirrors" 7685 SOURCE_MIRROR_URL = "http://example.com/my_source_mirror" 7686 7687 .. note:: 7688 7689 You can specify only a single URL in :term:`SOURCE_MIRROR_URL`. 7690 7691 :term:`SPDX_ARCHIVE_PACKAGED` 7692 This option allows to add to :term:`SPDX` output compressed archives 7693 of the files in the generated target packages. 7694 7695 Such archives are available in 7696 ``tmp/deploy/spdx/MACHINE/packages/packagename.tar.zst`` 7697 under the :term:`Build Directory`. 7698 7699 Enable this option as follows:: 7700 7701 SPDX_ARCHIVE_PACKAGED = "1" 7702 7703 According to our tests on release 4.1 "langdale", building 7704 ``core-image-minimal`` for the ``qemux86-64`` machine, enabling this 7705 option multiplied the size of the ``tmp/deploy/spdx`` directory by a 7706 factor of 13 (+1.6 GiB for this image), compared to just using the 7707 :ref:`ref-classes-create-spdx` class with no option. 7708 7709 Note that this option doesn't increase the size of :term:`SPDX` 7710 files in ``tmp/deploy/images/MACHINE``. 7711 7712 :term:`SPDX_ARCHIVE_SOURCES` 7713 This option allows to add to :term:`SPDX` output compressed archives 7714 of the sources for packages installed on the target. It currently 7715 only works when :term:`SPDX_INCLUDE_SOURCES` is set. 7716 7717 This is one way of fulfilling "source code access" license 7718 requirements. 7719 7720 Such source archives are available in 7721 ``tmp/deploy/spdx/MACHINE/recipes/recipe-packagename.tar.zst`` 7722 under the :term:`Build Directory`. 7723 7724 Enable this option as follows:: 7725 7726 SPDX_INCLUDE_SOURCES = "1" 7727 SPDX_ARCHIVE_SOURCES = "1" 7728 7729 According to our tests on release 4.1 "langdale", building 7730 ``core-image-minimal`` for the ``qemux86-64`` machine, enabling 7731 these options multiplied the size of the ``tmp/deploy/spdx`` 7732 directory by a factor of 11 (+1.4 GiB for this image), 7733 compared to just using the :ref:`ref-classes-create-spdx` 7734 class with no option. 7735 7736 Note that using this option only marginally increases the size 7737 of the :term:`SPDX` output in ``tmp/deploy/images/MACHINE/`` 7738 (+ 0.07\% with the tested image), compared to just enabling 7739 :term:`SPDX_INCLUDE_SOURCES`. 7740 7741 :term:`SPDX_CUSTOM_ANNOTATION_VARS` 7742 This option allows to associate `SPDX annotations 7743 <https://spdx.github.io/spdx-spec/v2.3/annotations/>`__ to a recipe, 7744 using the values of variables in the recipe:: 7745 7746 ANNOTATION1 = "First annotation for recipe" 7747 ANNOTATION2 = "Second annotation for recipe" 7748 SPDX_CUSTOM_ANNOTATION_VARS = "ANNOTATION1 ANNOTATION2" 7749 7750 This will add a new block to the recipe ``.sdpx.json`` output:: 7751 7752 "annotations": [ 7753 { 7754 "annotationDate": "2023-04-18T08:32:12Z", 7755 "annotationType": "OTHER", 7756 "annotator": "Tool: oe-spdx-creator - 1.0", 7757 "comment": "ANNOTATION1=First annotation for recipe" 7758 }, 7759 { 7760 "annotationDate": "2023-04-18T08:32:12Z", 7761 "annotationType": "OTHER", 7762 "annotator": "Tool: oe-spdx-creator - 1.0", 7763 "comment": "ANNOTATION2=Second annotation for recipe" 7764 } 7765 ], 7766 7767 :term:`SPDX_INCLUDE_SOURCES` 7768 This option allows to add a description of the source files used to build 7769 the host tools and the target packages, to the ``spdx.json`` files in 7770 ``tmp/deploy/spdx/MACHINE/recipes/`` under the :term:`Build Directory`. 7771 As a consequence, the ``spdx.json`` files under the ``by-namespace`` and 7772 ``packages`` subdirectories in ``tmp/deploy/spdx/MACHINE`` are also 7773 modified to include references to such source file descriptions. 7774 7775 Enable this option as follows:: 7776 7777 SPDX_INCLUDE_SOURCES = "1" 7778 7779 According to our tests on release 4.1 "langdale", building 7780 ``core-image-minimal`` for the ``qemux86-64`` machine, enabling 7781 this option multiplied the total size of the ``tmp/deploy/spdx`` 7782 directory by a factor of 3 (+291 MiB for this image), 7783 and the size of the ``IMAGE-MACHINE.spdx.tar.zst`` in 7784 ``tmp/deploy/images/MACHINE`` by a factor of 130 (+15 MiB for this 7785 image), compared to just using the :ref:`ref-classes-create-spdx` class 7786 with no option. 7787 7788 :term:`SPDX_PRETTY` 7789 This option makes the SPDX output more human-readable, using 7790 identation and newlines, instead of the default output in a 7791 single line:: 7792 7793 SPDX_PRETTY = "1" 7794 7795 The generated SPDX files are approximately 20% bigger, but 7796 this option is recommended if you want to inspect the SPDX 7797 output files with a text editor. 7798 7799 :term:`SPDXLICENSEMAP` 7800 Maps commonly used license names to their SPDX counterparts found in 7801 ``meta/files/common-licenses/``. For the default :term:`SPDXLICENSEMAP` 7802 mappings, see the ``meta/conf/licenses.conf`` file. 7803 7804 For additional information, see the :term:`LICENSE` 7805 variable. 7806 7807 :term:`SPECIAL_PKGSUFFIX` 7808 A list of prefixes for :term:`PN` used by the OpenEmbedded 7809 build system to create variants of recipes or packages. The list 7810 specifies the prefixes to strip off during certain circumstances such 7811 as the generation of the :term:`BPN` variable. 7812 7813 :term:`SPL_BINARY` 7814 The file type for the Secondary Program Loader (SPL). Some devices 7815 use an SPL from which to boot (e.g. the BeagleBone development 7816 board). For such cases, you can declare the file type of the SPL 7817 binary in the ``u-boot.inc`` include file, which is used in the 7818 U-Boot recipe. 7819 7820 The SPL file type is set to "null" by default in the ``u-boot.inc`` 7821 file as follows:: 7822 7823 # Some versions of u-boot build an SPL (Second Program Loader) image that 7824 # should be packaged along with the u-boot binary as well as placed in the 7825 # deploy directory. For those versions they can set the following variables 7826 # to allow packaging the SPL. 7827 SPL_BINARY ?= "" 7828 SPL_BINARYNAME ?= "${@os.path.basename(d.getVar("SPL_BINARY"))}" 7829 SPL_IMAGE ?= "${SPL_BINARYNAME}-${MACHINE}-${PV}-${PR}" 7830 SPL_SYMLINK ?= "${SPL_BINARYNAME}-${MACHINE}" 7831 7832 The :term:`SPL_BINARY` variable helps form 7833 various ``SPL_*`` variables used by the OpenEmbedded build system. 7834 7835 See the BeagleBone machine configuration example in the 7836 ":ref:`dev-manual/layers:adding a layer using the \`\`bitbake-layers\`\` script`" 7837 section in the Yocto Project Board Support Package Developer's Guide 7838 for additional information. 7839 7840 :term:`SPL_MKIMAGE_DTCOPTS` 7841 Options for the device tree compiler passed to ``mkimage -D`` feature 7842 while creating a FIT image with the :ref:`ref-classes-uboot-sign` 7843 class. If :term:`SPL_MKIMAGE_DTCOPTS` is not set then the 7844 :ref:`ref-classes-uboot-sign` class will not pass the ``-D`` option 7845 to ``mkimage``. 7846 7847 The default value is set to "" by the :ref:`ref-classes-uboot-config` 7848 class. 7849 7850 :term:`SPL_SIGN_ENABLE` 7851 Enable signing of the U-Boot FIT image. The default value is "0". 7852 This variable is used by the :ref:`ref-classes-uboot-sign` class. 7853 7854 :term:`SPL_SIGN_KEYDIR` 7855 Location of the directory containing the RSA key and certificate used for 7856 signing the U-Boot FIT image, used by the :ref:`ref-classes-uboot-sign` 7857 class. 7858 7859 :term:`SPL_SIGN_KEYNAME` 7860 The name of keys used by the :ref:`ref-classes-kernel-fitimage` class 7861 for signing U-Boot FIT image stored in the :term:`SPL_SIGN_KEYDIR` 7862 directory. If we have for example a ``dev.key`` key and a ``dev.crt`` 7863 certificate stored in the :term:`SPL_SIGN_KEYDIR` directory, you will 7864 have to set :term:`SPL_SIGN_KEYNAME` to ``dev``. 7865 7866 :term:`SPLASH` 7867 This variable, used by the :ref:`ref-classes-image` class, allows 7868 to choose splashscreen applications. Set it to the names of packages 7869 for such applications to use. This variable is set by default to 7870 ``psplash``. 7871 7872 :term:`SPLASH_IMAGES` 7873 This variable, used by the ``psplash`` recipe, allows to customize 7874 the default splashscreen image. 7875 7876 Specified images in PNG format are converted to ``.h`` files by the recipe, 7877 and are included in the ``psplash`` binary, so you won't find them in 7878 the root filesystem. 7879 7880 To make such a change, it is recommended to customize the 7881 ``psplash`` recipe in a custom layer. Here is an example structure for 7882 an ``ACME`` board:: 7883 7884 meta-acme/recipes-core/psplash 7885 ├── files 7886 │ └── logo-acme.png 7887 └── psplash_%.bbappend 7888 7889 And here are the contents of the ``psplash_%.bbappend`` file in 7890 this example:: 7891 7892 SPLASH_IMAGES = "file://logo-acme.png;outsuffix=default" 7893 FILESEXTRAPATHS:prepend := "${THISDIR}/files:" 7894 7895 You could even add specific configuration options for ``psplash``, 7896 for example:: 7897 7898 EXTRA_OECONF += "--disable-startup-msg --enable-img-fullscreen" 7899 7900 For information on append files, see the 7901 ":ref:`dev-manual/layers:appending other layers metadata with your layer`" 7902 section. 7903 7904 :term:`SRCREV_FORMAT` 7905 See :term:`bitbake:SRCREV_FORMAT` in the BitBake manual. 7906 7907 :term:`SRC_URI` 7908 7909 See the BitBake manual for the initial description for this variable: 7910 :term:`bitbake:SRC_URI`. 7911 7912 The following features are added by OpenEmbedded and the Yocto Project. 7913 7914 There are standard and recipe-specific options. Here are standard ones: 7915 7916 - ``apply`` --- whether to apply the patch or not. The default 7917 action is to apply the patch. 7918 7919 - ``striplevel`` --- which striplevel to use when applying the 7920 patch. The default level is 1. 7921 7922 - ``patchdir`` --- specifies the directory in which the patch should 7923 be applied. The default is ``${``\ :term:`S`\ ``}``. 7924 7925 Here are options specific to recipes building code from a revision 7926 control system: 7927 7928 - ``mindate`` --- apply the patch only if 7929 :term:`SRCDATE` is equal to or greater than 7930 ``mindate``. 7931 7932 - ``maxdate`` --- apply the patch only if :term:`SRCDATE` is not later 7933 than ``maxdate``. 7934 7935 - ``minrev`` --- apply the patch only if :term:`SRCREV` is equal to or 7936 greater than ``minrev``. 7937 7938 - ``maxrev`` --- apply the patch only if :term:`SRCREV` is not later 7939 than ``maxrev``. 7940 7941 - ``rev`` --- apply the patch only if :term:`SRCREV` is equal to 7942 ``rev``. 7943 7944 - ``notrev`` --- apply the patch only if :term:`SRCREV` is not equal to 7945 ``rev``. 7946 7947 .. note:: 7948 7949 If you want the build system to pick up files specified through 7950 a :term:`SRC_URI` statement from your append file, you need to be 7951 sure to extend the :term:`FILESPATH` variable by also using the 7952 :term:`FILESEXTRAPATHS` variable from within your append file. 7953 7954 :term:`SRC_URI_OVERRIDES_PACKAGE_ARCH` 7955 By default, the OpenEmbedded build system automatically detects 7956 whether :term:`SRC_URI` contains files that are machine-specific. If so, 7957 the build system automatically changes :term:`PACKAGE_ARCH`. Setting this 7958 variable to "0" disables this behavior. 7959 7960 :term:`SRCDATE` 7961 The date of the source code used to build the package. This variable 7962 applies only if the source was fetched from a Source Code Manager 7963 (SCM). 7964 7965 :term:`SRCPV` 7966 Returns the version string of the current package. This string is 7967 used to help define the value of :term:`PV`. 7968 7969 The :term:`SRCPV` variable is defined in the ``meta/conf/bitbake.conf`` 7970 configuration file in the :term:`Source Directory` as 7971 follows:: 7972 7973 SRCPV = "${@bb.fetch2.get_srcrev(d)}" 7974 7975 Recipes that need to define :term:`PV` do so with the help of the 7976 :term:`SRCPV`. For example, the ``ofono`` recipe (``ofono_git.bb``) 7977 located in ``meta/recipes-connectivity`` in the Source Directory 7978 defines :term:`PV` as follows:: 7979 7980 PV = "0.12-git${SRCPV}" 7981 7982 :term:`SRCREV` 7983 The revision of the source code used to build the package. This 7984 variable applies to Subversion, Git, Mercurial, and Bazaar only. Note 7985 that if you want to build a fixed revision and you want to avoid 7986 performing a query on the remote repository every time BitBake parses 7987 your recipe, you should specify a :term:`SRCREV` that is a full revision 7988 identifier (e.g. the full SHA hash in git) and not just a tag. 7989 7990 .. note:: 7991 7992 For information on limitations when inheriting the latest revision 7993 of software using :term:`SRCREV`, see the :term:`AUTOREV` variable 7994 description and the 7995 ":ref:`dev-manual/packages:automatically incrementing a package version number`" 7996 section, which is in the Yocto Project Development Tasks Manual. 7997 7998 :term:`SRCTREECOVEREDTASKS` 7999 A list of tasks that are typically not relevant (and therefore skipped) 8000 when building using the :ref:`ref-classes-externalsrc` 8001 class. The default value as set in that class file is the set of tasks 8002 that are rarely needed when using external source:: 8003 8004 SRCTREECOVEREDTASKS ?= "do_patch do_unpack do_fetch" 8005 8006 The notable exception is when processing external kernel source as 8007 defined in the :ref:`ref-classes-kernel-yocto` class file (formatted for 8008 aesthetics):: 8009 8010 SRCTREECOVEREDTASKS += "\ 8011 do_validate_branches \ 8012 do_kernel_configcheck \ 8013 do_kernel_checkout \ 8014 do_fetch \ 8015 do_unpack \ 8016 do_patch \ 8017 " 8018 8019 See the associated :term:`EXTERNALSRC` and :term:`EXTERNALSRC_BUILD` 8020 variables for more information. 8021 8022 :term:`SSTATE_DIR` 8023 The directory for the shared state cache. 8024 8025 :term:`SSTATE_EXCLUDEDEPS_SYSROOT` 8026 This variable allows to specify indirect dependencies to exclude 8027 from sysroots, for example to avoid the situations when a dependency on 8028 any ``-native`` recipe will pull in all dependencies of that recipe 8029 in the recipe sysroot. This behaviour might not always be wanted, 8030 for example when that ``-native`` recipe depends on build tools 8031 that are not relevant for the current recipe. 8032 8033 This way, irrelevant dependencies are ignored, which could have 8034 prevented the reuse of prebuilt artifacts stored in the Shared 8035 State Cache. 8036 8037 :term:`SSTATE_EXCLUDEDEPS_SYSROOT` is evaluated as two regular 8038 expressions of recipe and dependency to ignore. An example 8039 is the rule in :oe_git:`meta/conf/layer.conf </openembedded-core/tree/meta/conf/layer.conf>`:: 8040 8041 # Nothing needs to depend on libc-initial 8042 # base-passwd/shadow-sysroot don't need their dependencies 8043 SSTATE_EXCLUDEDEPS_SYSROOT += "\ 8044 .*->.*-initial.* \ 8045 .*(base-passwd|shadow-sysroot)->.* \ 8046 " 8047 8048 The ``->`` substring represents the dependency between 8049 the two regular expressions. 8050 8051 :term:`SSTATE_MIRROR_ALLOW_NETWORK` 8052 If set to "1", allows fetches from mirrors that are specified in 8053 :term:`SSTATE_MIRRORS` to work even when 8054 fetching from the network is disabled by setting :term:`BB_NO_NETWORK` to 8055 "1". Using the :term:`SSTATE_MIRROR_ALLOW_NETWORK` variable is useful if 8056 you have set :term:`SSTATE_MIRRORS` to point to an internal server for 8057 your shared state cache, but you want to disable any other fetching 8058 from the network. 8059 8060 :term:`SSTATE_MIRRORS` 8061 Configures the OpenEmbedded build system to search other mirror 8062 locations for prebuilt cache data objects before building out the 8063 data. This variable works like fetcher :term:`MIRRORS` 8064 and :term:`PREMIRRORS` and points to the cache 8065 locations to check for the shared state (sstate) objects. 8066 8067 You can specify a filesystem directory or a remote URL such as HTTP 8068 or FTP. The locations you specify need to contain the shared state 8069 cache (sstate-cache) results from previous builds. The sstate-cache 8070 you point to can also be from builds on other machines. 8071 8072 When pointing to sstate build artifacts on another machine that uses 8073 a different GCC version for native builds, you must configure 8074 :term:`SSTATE_MIRRORS` with a regular expression that maps local search 8075 paths to server paths. The paths need to take into account 8076 :term:`NATIVELSBSTRING` set by the :ref:`ref-classes-uninative` class. 8077 For example, the following maps the local search path ``universal-4.9`` 8078 to the server-provided path server_url_sstate_path:: 8079 8080 SSTATE_MIRRORS ?= "file://universal-4.9/(.*) https://server_url_sstate_path/universal-4.8/\1" 8081 8082 If a mirror uses the same structure as 8083 :term:`SSTATE_DIR`, you need to add "PATH" at the 8084 end as shown in the examples below. The build system substitutes the 8085 correct path within the directory structure:: 8086 8087 SSTATE_MIRRORS ?= "\ 8088 file://.* https://someserver.tld/share/sstate/PATH;downloadfilename=PATH \ 8089 file://.* file:///some-local-dir/sstate/PATH" 8090 8091 :term:`SSTATE_SCAN_FILES` 8092 Controls the list of files the OpenEmbedded build system scans for 8093 hardcoded installation paths. The variable uses a space-separated 8094 list of filenames (not paths) with standard wildcard characters 8095 allowed. 8096 8097 During a build, the OpenEmbedded build system creates a shared state 8098 (sstate) object during the first stage of preparing the sysroots. 8099 That object is scanned for hardcoded paths for original installation 8100 locations. The list of files that are scanned for paths is controlled 8101 by the :term:`SSTATE_SCAN_FILES` variable. Typically, recipes add files 8102 they want to be scanned to the value of :term:`SSTATE_SCAN_FILES` rather 8103 than the variable being comprehensively set. The 8104 :ref:`ref-classes-sstate` class specifies the default list of files. 8105 8106 For details on the process, see the :ref:`ref-classes-staging` class. 8107 8108 :term:`STAGING_BASE_LIBDIR_NATIVE` 8109 Specifies the path to the ``/lib`` subdirectory of the sysroot 8110 directory for the build host. 8111 8112 :term:`STAGING_BASELIBDIR` 8113 Specifies the path to the ``/lib`` subdirectory of the sysroot 8114 directory for the target for which the current recipe is being built 8115 (:term:`STAGING_DIR_HOST`). 8116 8117 :term:`STAGING_BINDIR` 8118 Specifies the path to the ``/usr/bin`` subdirectory of the sysroot 8119 directory for the target for which the current recipe is being built 8120 (:term:`STAGING_DIR_HOST`). 8121 8122 :term:`STAGING_BINDIR_CROSS` 8123 Specifies the path to the directory containing binary configuration 8124 scripts. These scripts provide configuration information for other 8125 software that wants to make use of libraries or include files 8126 provided by the software associated with the script. 8127 8128 .. note:: 8129 8130 This style of build configuration has been largely replaced by 8131 ``pkg-config``. Consequently, if ``pkg-config`` is supported by the 8132 library to which you are linking, it is recommended you use 8133 ``pkg-config`` instead of a provided configuration script. 8134 8135 :term:`STAGING_BINDIR_NATIVE` 8136 Specifies the path to the ``/usr/bin`` subdirectory of the sysroot 8137 directory for the build host. 8138 8139 :term:`STAGING_DATADIR` 8140 Specifies the path to the ``/usr/share`` subdirectory of the sysroot 8141 directory for the target for which the current recipe is being built 8142 (:term:`STAGING_DIR_HOST`). 8143 8144 :term:`STAGING_DATADIR_NATIVE` 8145 Specifies the path to the ``/usr/share`` subdirectory of the sysroot 8146 directory for the build host. 8147 8148 :term:`STAGING_DIR` 8149 Helps construct the ``recipe-sysroots`` directory, which is used 8150 during packaging. 8151 8152 For information on how staging for recipe-specific sysroots occurs, 8153 see the :ref:`ref-tasks-populate_sysroot` 8154 task, the ":ref:`sdk-manual/extensible:sharing files between recipes`" 8155 section in the Yocto Project Development Tasks Manual, the 8156 ":ref:`overview-manual/concepts:configuration, compilation, and staging`" 8157 section in the Yocto Project Overview and Concepts Manual, and the 8158 :term:`SYSROOT_DIRS` variable. 8159 8160 .. note:: 8161 8162 Recipes should never write files directly under the :term:`STAGING_DIR` 8163 directory because the OpenEmbedded build system manages the 8164 directory automatically. Instead, files should be installed to 8165 ``${``\ :term:`D`\ ``}`` within your recipe's :ref:`ref-tasks-install` 8166 task and then the OpenEmbedded build system will stage a subset of 8167 those files into the sysroot. 8168 8169 :term:`STAGING_DIR_HOST` 8170 Specifies the path to the sysroot directory for the system on which 8171 the component is built to run (the system that hosts the component). 8172 For most recipes, this sysroot is the one in which that recipe's 8173 :ref:`ref-tasks-populate_sysroot` task copies 8174 files. Exceptions include ``-native`` recipes, where the 8175 :ref:`ref-tasks-populate_sysroot` task instead uses 8176 :term:`STAGING_DIR_NATIVE`. Depending on 8177 the type of recipe and the build target, :term:`STAGING_DIR_HOST` can 8178 have the following values: 8179 8180 - For recipes building for the target machine, the value is 8181 "${:term:`STAGING_DIR`}/${:term:`MACHINE`}". 8182 8183 - For native recipes building for the build host, the value is empty 8184 given the assumption that when building for the build host, the 8185 build host's own directories should be used. 8186 8187 .. note:: 8188 8189 ``-native`` recipes are not installed into host paths like such 8190 as ``/usr``. Rather, these recipes are installed into 8191 :term:`STAGING_DIR_NATIVE`. When compiling ``-native`` recipes, 8192 standard build environment variables such as 8193 :term:`CPPFLAGS` and 8194 :term:`CFLAGS` are set up so that both host paths 8195 and :term:`STAGING_DIR_NATIVE` are searched for libraries and 8196 headers using, for example, GCC's ``-isystem`` option. 8197 8198 Thus, the emphasis is that the ``STAGING_DIR*`` variables 8199 should be viewed as input variables by tasks such as 8200 :ref:`ref-tasks-configure`, 8201 :ref:`ref-tasks-compile`, and 8202 :ref:`ref-tasks-install`. Having the real system 8203 root correspond to :term:`STAGING_DIR_HOST` makes conceptual sense 8204 for ``-native`` recipes, as they make use of host headers and 8205 libraries. 8206 8207 :term:`STAGING_DIR_NATIVE` 8208 Specifies the path to the sysroot directory used when building 8209 components that run on the build host itself. 8210 8211 :term:`STAGING_DIR_TARGET` 8212 Specifies the path to the sysroot used for the system for which the 8213 component generates code. For components that do not generate code, 8214 which is the majority, :term:`STAGING_DIR_TARGET` is set to match 8215 :term:`STAGING_DIR_HOST`. 8216 8217 Some recipes build binaries that can run on the target system but those 8218 binaries in turn generate code for another different system (e.g. 8219 :ref:`ref-classes-cross-canadian` recipes). Using terminology from GNU, 8220 the primary system is referred to as the "HOST" and the secondary, or 8221 different, system is referred to as the "TARGET". Thus, the binaries 8222 run on the "HOST" system and generate binaries for the "TARGET" 8223 system. The :term:`STAGING_DIR_HOST` variable points to the sysroot used 8224 for the "HOST" system, while :term:`STAGING_DIR_TARGET` points to the 8225 sysroot used for the "TARGET" system. 8226 8227 :term:`STAGING_ETCDIR_NATIVE` 8228 Specifies the path to the ``/etc`` subdirectory of the sysroot 8229 directory for the build host. 8230 8231 :term:`STAGING_EXECPREFIXDIR` 8232 Specifies the path to the ``/usr`` subdirectory of the sysroot 8233 directory for the target for which the current recipe is being built 8234 (:term:`STAGING_DIR_HOST`). 8235 8236 :term:`STAGING_INCDIR` 8237 Specifies the path to the ``/usr/include`` subdirectory of the 8238 sysroot directory for the target for which the current recipe being 8239 built (:term:`STAGING_DIR_HOST`). 8240 8241 :term:`STAGING_INCDIR_NATIVE` 8242 Specifies the path to the ``/usr/include`` subdirectory of the 8243 sysroot directory for the build host. 8244 8245 :term:`STAGING_KERNEL_BUILDDIR` 8246 Points to the directory containing the kernel build artifacts. 8247 Recipes building software that needs to access kernel build artifacts 8248 (e.g. ``systemtap-uprobes``) can look in the directory specified with 8249 the :term:`STAGING_KERNEL_BUILDDIR` variable to find these artifacts 8250 after the kernel has been built. 8251 8252 :term:`STAGING_KERNEL_DIR` 8253 The directory with kernel headers that are required to build 8254 out-of-tree modules. 8255 8256 :term:`STAGING_LIBDIR` 8257 Specifies the path to the ``/usr/lib`` subdirectory of the sysroot 8258 directory for the target for which the current recipe is being built 8259 (:term:`STAGING_DIR_HOST`). 8260 8261 :term:`STAGING_LIBDIR_NATIVE` 8262 Specifies the path to the ``/usr/lib`` subdirectory of the sysroot 8263 directory for the build host. 8264 8265 :term:`STAMP` 8266 Specifies the base path used to create recipe stamp files. The path 8267 to an actual stamp file is constructed by evaluating this string and 8268 then appending additional information. Currently, the default 8269 assignment for :term:`STAMP` as set in the ``meta/conf/bitbake.conf`` 8270 file is:: 8271 8272 STAMP = "${STAMPS_DIR}/${MULTIMACH_TARGET_SYS}/${PN}/${EXTENDPE}${PV}-${PR}" 8273 8274 For information on how BitBake uses stamp files to determine if a 8275 task should be rerun, see the 8276 ":ref:`overview-manual/concepts:stamp files and the rerunning of tasks`" 8277 section in the Yocto Project Overview and Concepts Manual. 8278 8279 See :term:`STAMPS_DIR`, 8280 :term:`MULTIMACH_TARGET_SYS`, 8281 :term:`PN`, :term:`EXTENDPE`, 8282 :term:`PV`, and :term:`PR` for related variable 8283 information. 8284 8285 :term:`STAMPCLEAN` 8286 See :term:`bitbake:STAMPCLEAN` in the BitBake manual. 8287 8288 :term:`STAMPS_DIR` 8289 Specifies the base directory in which the OpenEmbedded build system 8290 places stamps. The default directory is ``${TMPDIR}/stamps``. 8291 8292 :term:`STRIP` 8293 The minimal command and arguments to run ``strip``, which is used to 8294 strip symbols. 8295 8296 :term:`SUMMARY` 8297 The short (72 characters or less) summary of the binary package for 8298 packaging systems such as ``opkg``, ``rpm``, or ``dpkg``. By default, 8299 :term:`SUMMARY` is used to define the 8300 :term:`DESCRIPTION` variable if :term:`DESCRIPTION` is 8301 not set in the recipe. 8302 8303 :term:`SVNDIR` 8304 The directory in which files checked out of a Subversion system are 8305 stored. 8306 8307 :term:`SYSLINUX_DEFAULT_CONSOLE` 8308 Specifies the kernel boot default console. If you want to use a 8309 console other than the default, set this variable in your recipe as 8310 follows where "X" is the console number you want to use:: 8311 8312 SYSLINUX_DEFAULT_CONSOLE = "console=ttyX" 8313 8314 The :ref:`ref-classes-syslinux` class initially sets 8315 this variable to null but then checks for a value later. 8316 8317 :term:`SYSLINUX_OPTS` 8318 Lists additional options to add to the syslinux file. You need to set 8319 this variable in your recipe. If you want to list multiple options, 8320 separate the options with a semicolon character (``;``). 8321 8322 The :ref:`ref-classes-syslinux` class uses this variable 8323 to create a set of options. 8324 8325 :term:`SYSLINUX_SERIAL` 8326 Specifies the alternate serial port or turns it off. To turn off 8327 serial, set this variable to an empty string in your recipe. The 8328 variable's default value is set in the 8329 :ref:`ref-classes-syslinux` class as follows:: 8330 8331 SYSLINUX_SERIAL ?= "0 115200" 8332 8333 The class checks for and uses the variable as needed. 8334 8335 :term:`SYSLINUX_SERIAL_TTY` 8336 Specifies the alternate console=tty... kernel boot argument. The 8337 variable's default value is set in the :ref:`ref-classes-syslinux` 8338 class as follows:: 8339 8340 SYSLINUX_SERIAL_TTY ?= "console=ttyS0,115200" 8341 8342 The class checks for and uses the variable as needed. 8343 8344 :term:`SYSLINUX_SPLASH` 8345 An ``.LSS`` file used as the background for the VGA boot menu when 8346 you use the boot menu. You need to set this variable in your recipe. 8347 8348 The :ref:`ref-classes-syslinux` class checks for this 8349 variable and if found, the OpenEmbedded build system installs the 8350 splash screen. 8351 8352 :term:`SYSROOT_DESTDIR` 8353 Points to the temporary directory under the work directory (default 8354 "``${``\ :term:`WORKDIR`\ ``}/sysroot-destdir``") 8355 where the files populated into the sysroot are assembled during the 8356 :ref:`ref-tasks-populate_sysroot` task. 8357 8358 :term:`SYSROOT_DIRS` 8359 Directories that are staged into the sysroot by the 8360 :ref:`ref-tasks-populate_sysroot` task. By 8361 default, the following directories are staged:: 8362 8363 SYSROOT_DIRS = " \ 8364 ${includedir} \ 8365 ${libdir} \ 8366 ${base_libdir} \ 8367 ${nonarch_base_libdir} \ 8368 ${datadir} \ 8369 /sysroot-only \ 8370 " 8371 8372 :term:`SYSROOT_DIRS_IGNORE` 8373 Directories that are not staged into the sysroot by the 8374 :ref:`ref-tasks-populate_sysroot` task. You 8375 can use this variable to exclude certain subdirectories of 8376 directories listed in :term:`SYSROOT_DIRS` from 8377 staging. By default, the following directories are not staged:: 8378 8379 SYSROOT_DIRS_IGNORE = " \ 8380 ${mandir} \ 8381 ${docdir} \ 8382 ${infodir} \ 8383 ${datadir}/X11/locale \ 8384 ${datadir}/applications \ 8385 ${datadir}/bash-completion \ 8386 ${datadir}/fonts \ 8387 ${datadir}/gtk-doc/html \ 8388 ${datadir}/installed-tests \ 8389 ${datadir}/locale \ 8390 ${datadir}/pixmaps \ 8391 ${datadir}/terminfo \ 8392 ${libdir}/${BPN}/ptest \ 8393 " 8394 8395 :term:`SYSROOT_DIRS_NATIVE` 8396 Extra directories staged into the sysroot by the 8397 :ref:`ref-tasks-populate_sysroot` task for 8398 ``-native`` recipes, in addition to those specified in 8399 :term:`SYSROOT_DIRS`. By default, the following 8400 extra directories are staged:: 8401 8402 SYSROOT_DIRS_NATIVE = " \ 8403 ${bindir} \ 8404 ${sbindir} \ 8405 ${base_bindir} \ 8406 ${base_sbindir} \ 8407 ${libexecdir} \ 8408 ${sysconfdir} \ 8409 ${localstatedir} \ 8410 " 8411 8412 .. note:: 8413 8414 Programs built by ``-native`` recipes run directly from the sysroot 8415 (:term:`STAGING_DIR_NATIVE`), which is why additional directories 8416 containing program executables and supporting files need to be staged. 8417 8418 :term:`SYSROOT_PREPROCESS_FUNCS` 8419 A list of functions to execute after files are staged into the 8420 sysroot. These functions are usually used to apply additional 8421 processing on the staged files, or to stage additional files. 8422 8423 :term:`SYSTEMD_AUTO_ENABLE` 8424 When inheriting the :ref:`ref-classes-systemd` class, 8425 this variable specifies whether the specified service in 8426 :term:`SYSTEMD_SERVICE` should start 8427 automatically or not. By default, the service is enabled to 8428 automatically start at boot time. The default setting is in the 8429 :ref:`ref-classes-systemd` class as follows:: 8430 8431 SYSTEMD_AUTO_ENABLE ??= "enable" 8432 8433 You can disable the service by setting the variable to "disable". 8434 8435 :term:`SYSTEMD_BOOT_CFG` 8436 When :term:`EFI_PROVIDER` is set to 8437 "systemd-boot", the :term:`SYSTEMD_BOOT_CFG` variable specifies the 8438 configuration file that should be used. By default, the 8439 :ref:`ref-classes-systemd-boot` class sets the 8440 :term:`SYSTEMD_BOOT_CFG` as follows:: 8441 8442 SYSTEMD_BOOT_CFG ?= "${S}/loader.conf" 8443 8444 For information on Systemd-boot, see the `Systemd-boot 8445 documentation <https://www.freedesktop.org/wiki/Software/systemd/systemd-boot/>`__. 8446 8447 :term:`SYSTEMD_BOOT_ENTRIES` 8448 When :term:`EFI_PROVIDER` is set to 8449 "systemd-boot", the :term:`SYSTEMD_BOOT_ENTRIES` variable specifies a 8450 list of entry files (``*.conf``) to install that contain one boot 8451 entry per file. By default, the :ref:`ref-classes-systemd-boot` class 8452 sets the :term:`SYSTEMD_BOOT_ENTRIES` as follows:: 8453 8454 SYSTEMD_BOOT_ENTRIES ?= "" 8455 8456 For information on Systemd-boot, see the `Systemd-boot 8457 documentation <https://www.freedesktop.org/wiki/Software/systemd/systemd-boot/>`__. 8458 8459 :term:`SYSTEMD_BOOT_TIMEOUT` 8460 When :term:`EFI_PROVIDER` is set to 8461 "systemd-boot", the :term:`SYSTEMD_BOOT_TIMEOUT` variable specifies the 8462 boot menu timeout in seconds. By default, the 8463 :ref:`ref-classes-systemd-boot` class sets the 8464 :term:`SYSTEMD_BOOT_TIMEOUT` as follows:: 8465 8466 SYSTEMD_BOOT_TIMEOUT ?= "10" 8467 8468 For information on Systemd-boot, see the `Systemd-boot 8469 documentation <https://www.freedesktop.org/wiki/Software/systemd/systemd-boot/>`__. 8470 8471 :term:`SYSTEMD_DEFAULT_TARGET` 8472 8473 This variable allows to set the default unit that systemd starts at bootup. 8474 Usually, this is either ``multi-user.target`` or ``graphical.target``. 8475 This works by creating a ``default.target`` symbolic link to the chosen systemd 8476 target file. 8477 8478 See `systemd's documentation 8479 <https://www.freedesktop.org/software/systemd/man/systemd.special.html>`__ 8480 for details. 8481 8482 For example, this variable is used in the :oe_git:`core-image-minimal-xfce.bb 8483 </meta-openembedded/tree/meta-xfce/recipes-core/images/core-image-minimal-xfce.bb>` 8484 recipe:: 8485 8486 SYSTEMD_DEFAULT_TARGET = "graphical.target" 8487 8488 :term:`SYSTEMD_PACKAGES` 8489 When inheriting the :ref:`ref-classes-systemd` class, 8490 this variable locates the systemd unit files when they are not found 8491 in the main recipe's package. By default, the :term:`SYSTEMD_PACKAGES` 8492 variable is set such that the systemd unit files are assumed to 8493 reside in the recipes main package:: 8494 8495 SYSTEMD_PACKAGES ?= "${PN}" 8496 8497 If these unit files are not in this recipe's main package, you need 8498 to use :term:`SYSTEMD_PACKAGES` to list the package or packages in which 8499 the build system can find the systemd unit files. 8500 8501 :term:`SYSTEMD_SERVICE` 8502 When inheriting the :ref:`ref-classes-systemd` class, 8503 this variable specifies the systemd service name for a package. 8504 8505 Multiple services can be specified, each one separated by a space. 8506 8507 When you specify this file in your recipe, use a package name 8508 override to indicate the package to which the value applies. Here is 8509 an example from the connman recipe:: 8510 8511 SYSTEMD_SERVICE:${PN} = "connman.service" 8512 8513 The package overrides that can be specified are directly related to the value of 8514 :term:`SYSTEMD_PACKAGES`. Overrides not included in :term:`SYSTEMD_PACKAGES` 8515 will be silently ignored. 8516 8517 :term:`SYSVINIT_ENABLED_GETTYS` 8518 When using :ref:`SysVinit <dev-manual/new-recipe:enabling system services>`, 8519 specifies a space-separated list of the virtual terminals that should 8520 run a :wikipedia:`getty <Getty_(Unix)>` (allowing login), assuming 8521 :term:`USE_VT` is not set to "0". 8522 8523 The default value for :term:`SYSVINIT_ENABLED_GETTYS` is "1" (i.e. only 8524 run a getty on the first virtual terminal). 8525 8526 :term:`T` 8527 This variable points to a directory were BitBake places temporary 8528 files, which consist mostly of task logs and scripts, when building a 8529 particular recipe. The variable is typically set as follows:: 8530 8531 T = "${WORKDIR}/temp" 8532 8533 The :term:`WORKDIR` is the directory into which 8534 BitBake unpacks and builds the recipe. The default ``bitbake.conf`` 8535 file sets this variable. 8536 8537 The :term:`T` variable is not to be confused with the 8538 :term:`TMPDIR` variable, which points to the root of 8539 the directory tree where BitBake places the output of an entire 8540 build. 8541 8542 :term:`TARGET_ARCH` 8543 The target machine's architecture. The OpenEmbedded build system 8544 supports many architectures. Here is an example list of architectures 8545 supported. This list is by no means complete as the architecture is 8546 configurable: 8547 8548 - arm 8549 - i586 8550 - x86_64 8551 - powerpc 8552 - powerpc64 8553 - mips 8554 - mipsel 8555 8556 For additional information on machine architectures, see the 8557 :term:`TUNE_ARCH` variable. 8558 8559 :term:`TARGET_AS_ARCH` 8560 Specifies architecture-specific assembler flags for the target 8561 system. :term:`TARGET_AS_ARCH` is initialized from 8562 :term:`TUNE_ASARGS` by default in the BitBake 8563 configuration file (``meta/conf/bitbake.conf``):: 8564 8565 TARGET_AS_ARCH = "${TUNE_ASARGS}" 8566 8567 :term:`TARGET_CC_ARCH` 8568 Specifies architecture-specific C compiler flags for the target 8569 system. :term:`TARGET_CC_ARCH` is initialized from 8570 :term:`TUNE_CCARGS` by default. 8571 8572 .. note:: 8573 8574 It is a common workaround to append :term:`LDFLAGS` to 8575 :term:`TARGET_CC_ARCH` in recipes that build software for the target that 8576 would not otherwise respect the exported :term:`LDFLAGS` variable. 8577 8578 :term:`TARGET_CC_KERNEL_ARCH` 8579 This is a specific kernel compiler flag for a CPU or Application 8580 Binary Interface (ABI) tune. The flag is used rarely and only for 8581 cases where a userspace :term:`TUNE_CCARGS` is not 8582 compatible with the kernel compilation. The :term:`TARGET_CC_KERNEL_ARCH` 8583 variable allows the kernel (and associated modules) to use a 8584 different configuration. See the 8585 ``meta/conf/machine/include/arm/feature-arm-thumb.inc`` file in the 8586 :term:`Source Directory` for an example. 8587 8588 :term:`TARGET_CFLAGS` 8589 Specifies the flags to pass to the C compiler when building for the 8590 target. When building in the target context, 8591 :term:`CFLAGS` is set to the value of this variable by 8592 default. 8593 8594 Additionally, the SDK's environment setup script sets the :term:`CFLAGS` 8595 variable in the environment to the :term:`TARGET_CFLAGS` value so that 8596 executables built using the SDK also have the flags applied. 8597 8598 :term:`TARGET_CPPFLAGS` 8599 Specifies the flags to pass to the C pre-processor (i.e. to both the 8600 C and the C++ compilers) when building for the target. When building 8601 in the target context, :term:`CPPFLAGS` is set to the 8602 value of this variable by default. 8603 8604 Additionally, the SDK's environment setup script sets the 8605 :term:`CPPFLAGS` variable in the environment to the :term:`TARGET_CPPFLAGS` 8606 value so that executables built using the SDK also have the flags 8607 applied. 8608 8609 :term:`TARGET_CXXFLAGS` 8610 Specifies the flags to pass to the C++ compiler when building for the 8611 target. When building in the target context, 8612 :term:`CXXFLAGS` is set to the value of this variable 8613 by default. 8614 8615 Additionally, the SDK's environment setup script sets the 8616 :term:`CXXFLAGS` variable in the environment to the :term:`TARGET_CXXFLAGS` 8617 value so that executables built using the SDK also have the flags 8618 applied. 8619 8620 :term:`TARGET_FPU` 8621 Specifies the method for handling FPU code. For FPU-less targets, 8622 which include most ARM CPUs, the variable must be set to "soft". If 8623 not, the kernel emulation gets used, which results in a performance 8624 penalty. 8625 8626 :term:`TARGET_LD_ARCH` 8627 Specifies architecture-specific linker flags for the target system. 8628 :term:`TARGET_LD_ARCH` is initialized from 8629 :term:`TUNE_LDARGS` by default in the BitBake 8630 configuration file (``meta/conf/bitbake.conf``):: 8631 8632 TARGET_LD_ARCH = "${TUNE_LDARGS}" 8633 8634 :term:`TARGET_LDFLAGS` 8635 Specifies the flags to pass to the linker when building for the 8636 target. When building in the target context, 8637 :term:`LDFLAGS` is set to the value of this variable 8638 by default. 8639 8640 Additionally, the SDK's environment setup script sets the 8641 :term:`LDFLAGS` variable in the environment to the 8642 :term:`TARGET_LDFLAGS` value so that executables built using the SDK also 8643 have the flags applied. 8644 8645 :term:`TARGET_OS` 8646 Specifies the target's operating system. The variable can be set to 8647 "linux" for glibc-based systems (GNU C Library) and to "linux-musl" 8648 for musl libc. For ARM/EABI targets, the possible values are 8649 "linux-gnueabi" and "linux-musleabi". 8650 8651 :term:`TARGET_PREFIX` 8652 Specifies the prefix used for the toolchain binary target tools. 8653 8654 Depending on the type of recipe and the build target, 8655 :term:`TARGET_PREFIX` is set as follows: 8656 8657 - For recipes building for the target machine, the value is 8658 "${:term:`TARGET_SYS`}-". 8659 8660 - For native recipes, the build system sets the variable to the 8661 value of :term:`BUILD_PREFIX`. 8662 8663 - For native SDK recipes (:ref:`ref-classes-nativesdk`), 8664 the build system sets the variable to the value of :term:`SDK_PREFIX`. 8665 8666 :term:`TARGET_SYS` 8667 Specifies the system, including the architecture and the operating 8668 system, for which the build is occurring in the context of the 8669 current recipe. 8670 8671 The OpenEmbedded build system automatically sets this variable based 8672 on :term:`TARGET_ARCH`, 8673 :term:`TARGET_VENDOR`, and 8674 :term:`TARGET_OS` variables. 8675 8676 .. note:: 8677 8678 You do not need to set the :term:`TARGET_SYS` variable yourself. 8679 8680 Consider these two examples: 8681 8682 - Given a native recipe on a 32-bit, x86 machine running Linux, the 8683 value is "i686-linux". 8684 8685 - Given a recipe being built for a little-endian, MIPS target 8686 running Linux, the value might be "mipsel-linux". 8687 8688 :term:`TARGET_VENDOR` 8689 Specifies the name of the target vendor. 8690 8691 :term:`TCLIBC` 8692 Specifies the GNU standard C library (``libc``) variant to use during 8693 the build process. 8694 8695 You can select "glibc", "musl", "newlib", or "baremetal". 8696 8697 :term:`TCLIBCAPPEND` 8698 Specifies a suffix to be appended onto the :term:`TMPDIR` value. The 8699 suffix identifies the ``libc`` variant for building. When you are 8700 building for multiple variants with the same :term:`Build Directory`, 8701 this mechanism ensures that output for different ``libc`` variants is 8702 kept separate to avoid potential conflicts. 8703 8704 In the ``defaultsetup.conf`` file, the default value of 8705 :term:`TCLIBCAPPEND` is "-${TCLIBC}". However, distros such as poky, 8706 which normally only support one ``libc`` variant, set 8707 :term:`TCLIBCAPPEND` to "" in their distro configuration file resulting 8708 in no suffix being applied. 8709 8710 :term:`TCMODE` 8711 Specifies the toolchain selector. :term:`TCMODE` controls the 8712 characteristics of the generated packages and images by telling the 8713 OpenEmbedded build system which toolchain profile to use. By default, 8714 the OpenEmbedded build system builds its own internal toolchain. The 8715 variable's default value is "default", which uses that internal 8716 toolchain. 8717 8718 .. note:: 8719 8720 If :term:`TCMODE` is set to a value other than "default", then it is your 8721 responsibility to ensure that the toolchain is compatible with the 8722 default toolchain. Using older or newer versions of these 8723 components might cause build problems. See 8724 :doc:`Release Information </migration-guides/index>` for your 8725 version of the Yocto Project, to find the specific components with 8726 which the toolchain must be compatible. 8727 8728 The :term:`TCMODE` variable is similar to :term:`TCLIBC`, 8729 which controls the variant of the GNU standard C library (``libc``) 8730 used during the build process: ``glibc`` or ``musl``. 8731 8732 With additional layers, it is possible to use a pre-compiled external 8733 toolchain. One example is the Sourcery G++ Toolchain. The support for 8734 this toolchain resides in the separate Mentor Graphics 8735 ``meta-sourcery`` layer at 8736 https://github.com/MentorEmbedded/meta-sourcery/. 8737 8738 The layer's ``README`` file contains information on how to use the 8739 Sourcery G++ Toolchain as an external toolchain. You will have to 8740 add the layer to your ``bblayers.conf`` file and then set the 8741 :term:`EXTERNAL_TOOLCHAIN` variable in your ``local.conf`` file to 8742 the location of the toolchain. 8743 8744 The fundamentals used for this example apply to any external 8745 toolchain. You can use ``meta-sourcery`` as a template for adding 8746 support for other external toolchains. 8747 8748 In addition to toolchain configuration, you will also need a 8749 corresponding toolchain recipe file. This recipe file needs to package 8750 up any pre-built objects in the toolchain such as ``libgcc``, 8751 ``libstdcc++``, any locales, and ``libc``. 8752 8753 :term:`TC_CXX_RUNTIME` 8754 Specifies the C/C++ STL and runtime variant to use during 8755 the build process. Default value is 'gnu' 8756 8757 You can select "gnu", "llvm", or "android". 8758 8759 :term:`TEMPLATECONF` 8760 Specifies the directory used by the build system to find templates 8761 from which to build the ``bblayers.conf`` and ``local.conf`` files. 8762 Use this variable if you wish to customize such files, and the default 8763 BitBake targets shown when sourcing the ``oe-init-build-env`` script. 8764 8765 For details, see the 8766 :ref:`dev-manual/custom-template-configuration-directory:creating a custom template configuration directory` 8767 section in the Yocto Project Development Tasks manual. 8768 8769 .. note:: 8770 8771 You must set this variable in the external environment in order 8772 for it to work. 8773 8774 :term:`TEST_EXPORT_DIR` 8775 The location the OpenEmbedded build system uses to export tests when 8776 the :term:`TEST_EXPORT_ONLY` variable is set 8777 to "1". 8778 8779 The :term:`TEST_EXPORT_DIR` variable defaults to 8780 ``"${TMPDIR}/testimage/${PN}"``. 8781 8782 :term:`TEST_EXPORT_ONLY` 8783 Specifies to export the tests only. Set this variable to "1" if you 8784 do not want to run the tests but you want them to be exported in a 8785 manner that you to run them outside of the build system. 8786 8787 :term:`TEST_LOG_DIR` 8788 Holds the SSH log and the boot log for QEMU machines. The 8789 :term:`TEST_LOG_DIR` variable defaults to ``"${WORKDIR}/testimage"``. 8790 8791 .. note:: 8792 8793 Actual test results reside in the task log (``log.do_testimage``), 8794 which is in the ``${WORKDIR}/temp/`` directory. 8795 8796 :term:`TEST_POWERCONTROL_CMD` 8797 For automated hardware testing, specifies the command to use to 8798 control the power of the target machine under test. Typically, this 8799 command would point to a script that performs the appropriate action 8800 (e.g. interacting with a web-enabled power strip). The specified 8801 command should expect to receive as the last argument "off", "on" or 8802 "cycle" specifying to power off, on, or cycle (power off and then 8803 power on) the device, respectively. 8804 8805 :term:`TEST_POWERCONTROL_EXTRA_ARGS` 8806 For automated hardware testing, specifies additional arguments to 8807 pass through to the command specified in 8808 :term:`TEST_POWERCONTROL_CMD`. Setting 8809 :term:`TEST_POWERCONTROL_EXTRA_ARGS` is optional. You can use it if you 8810 wish, for example, to separate the machine-specific and 8811 non-machine-specific parts of the arguments. 8812 8813 :term:`TEST_QEMUBOOT_TIMEOUT` 8814 The time in seconds allowed for an image to boot before automated 8815 runtime tests begin to run against an image. The default timeout 8816 period to allow the boot process to reach the login prompt is 500 8817 seconds. You can specify a different value in the ``local.conf`` 8818 file. 8819 8820 For more information on testing images, see the 8821 ":ref:`dev-manual/runtime-testing:performing automated runtime testing`" 8822 section in the Yocto Project Development Tasks Manual. 8823 8824 :term:`TEST_SERIALCONTROL_CMD` 8825 For automated hardware testing, specifies the command to use to 8826 connect to the serial console of the target machine under test. This 8827 command simply needs to connect to the serial console and forward 8828 that connection to standard input and output as any normal terminal 8829 program does. 8830 8831 For example, to use the Picocom terminal program on serial device 8832 ``/dev/ttyUSB0`` at 115200bps, you would set the variable as follows:: 8833 8834 TEST_SERIALCONTROL_CMD = "picocom /dev/ttyUSB0 -b 115200" 8835 8836 :term:`TEST_SERIALCONTROL_EXTRA_ARGS` 8837 For automated hardware testing, specifies additional arguments to 8838 pass through to the command specified in 8839 :term:`TEST_SERIALCONTROL_CMD`. Setting 8840 :term:`TEST_SERIALCONTROL_EXTRA_ARGS` is optional. You can use it if you 8841 wish, for example, to separate the machine-specific and 8842 non-machine-specific parts of the command. 8843 8844 :term:`TEST_SERVER_IP` 8845 The IP address of the build machine (host machine). This IP address 8846 is usually automatically detected. However, if detection fails, this 8847 variable needs to be set to the IP address of the build machine (i.e. 8848 where the build is taking place). 8849 8850 .. note:: 8851 8852 The :term:`TEST_SERVER_IP` variable is only used for a small number of 8853 tests such as the "dnf" test suite, which needs to download packages 8854 from ``WORKDIR/oe-rootfs-repo``. 8855 8856 :term:`TEST_SUITES` 8857 An ordered list of tests (modules) to run against an image when 8858 performing automated runtime testing. 8859 8860 The OpenEmbedded build system provides a core set of tests that can 8861 be used against images. 8862 8863 .. note:: 8864 8865 Currently, there is only support for running these tests under 8866 QEMU. 8867 8868 Tests include ``ping``, ``ssh``, ``df`` among others. You can add 8869 your own tests to the list of tests by appending :term:`TEST_SUITES` as 8870 follows:: 8871 8872 TEST_SUITES:append = " mytest" 8873 8874 Alternatively, you can 8875 provide the "auto" option to have all applicable tests run against 8876 the image:: 8877 8878 TEST_SUITES:append = " auto" 8879 8880 Using this option causes the 8881 build system to automatically run tests that are applicable to the 8882 image. Tests that are not applicable are skipped. 8883 8884 The order in which tests are run is important. Tests that depend on 8885 another test must appear later in the list than the test on which 8886 they depend. For example, if you append the list of tests with two 8887 tests (``test_A`` and ``test_B``) where ``test_B`` is dependent on 8888 ``test_A``, then you must order the tests as follows:: 8889 8890 TEST_SUITES = "test_A test_B" 8891 8892 For more information on testing images, see the 8893 ":ref:`dev-manual/runtime-testing:performing automated runtime testing`" 8894 section in the Yocto Project Development Tasks Manual. 8895 8896 :term:`TEST_TARGET` 8897 Specifies the target controller to use when running tests against a 8898 test image. The default controller to use is "qemu":: 8899 8900 TEST_TARGET = "qemu" 8901 8902 A target controller is a class that defines how an image gets 8903 deployed on a target and how a target is started. A layer can extend 8904 the controllers by adding a module in the layer's 8905 ``/lib/oeqa/controllers`` directory and by inheriting the 8906 ``BaseTarget`` class, which is an abstract class that cannot be used 8907 as a value of :term:`TEST_TARGET`. 8908 8909 You can provide the following arguments with :term:`TEST_TARGET`: 8910 8911 - *"qemu":* Boots a QEMU image and runs the tests. See the 8912 ":ref:`dev-manual/runtime-testing:enabling runtime tests on qemu`" section 8913 in the Yocto Project Development Tasks Manual for more 8914 information. 8915 8916 - *"simpleremote":* Runs the tests on target hardware that is 8917 already up and running. The hardware can be on the network or it 8918 can be a device running an image on QEMU. You must also set 8919 :term:`TEST_TARGET_IP` when you use 8920 "simpleremote". 8921 8922 .. note:: 8923 8924 This argument is defined in 8925 ``meta/lib/oeqa/controllers/simpleremote.py``. 8926 8927 For information on running tests on hardware, see the 8928 ":ref:`dev-manual/runtime-testing:enabling runtime tests on hardware`" 8929 section in the Yocto Project Development Tasks Manual. 8930 8931 :term:`TEST_TARGET_IP` 8932 The IP address of your hardware under test. The :term:`TEST_TARGET_IP` 8933 variable has no effect when :term:`TEST_TARGET` is 8934 set to "qemu". 8935 8936 When you specify the IP address, you can also include a port. Here is 8937 an example:: 8938 8939 TEST_TARGET_IP = "192.168.1.4:2201" 8940 8941 Specifying a port is 8942 useful when SSH is started on a non-standard port or in cases when 8943 your hardware under test is behind a firewall or network that is not 8944 directly accessible from your host and you need to do port address 8945 translation. 8946 8947 :term:`TESTIMAGE_AUTO` 8948 Automatically runs the series of automated tests for images when an 8949 image is successfully built. Setting :term:`TESTIMAGE_AUTO` to "1" causes 8950 any image that successfully builds to automatically boot under QEMU. 8951 Using the variable also adds in dependencies so that any SDK for 8952 which testing is requested is automatically built first. 8953 8954 These tests are written in Python making use of the ``unittest`` 8955 module, and the majority of them run commands on the target system 8956 over ``ssh``. You can set this variable to "1" in your ``local.conf`` 8957 file in the :term:`Build Directory` to have the 8958 OpenEmbedded build system automatically run these tests after an 8959 image successfully builds: 8960 8961 TESTIMAGE_AUTO = "1" 8962 8963 For more information 8964 on enabling, running, and writing these tests, see the 8965 ":ref:`dev-manual/runtime-testing:performing automated runtime testing`" 8966 section in the Yocto Project Development Tasks Manual and the 8967 ":ref:`ref-classes-testimage`" section. 8968 8969 :term:`THISDIR` 8970 The directory in which the file BitBake is currently parsing is 8971 located. Do not manually set this variable. 8972 8973 :term:`TIME` 8974 The time the build was started. Times appear using the hour, minute, 8975 and second (HMS) format (e.g. "140159" for one minute and fifty-nine 8976 seconds past 1400 hours). 8977 8978 :term:`TMPDIR` 8979 This variable is the base directory the OpenEmbedded build system 8980 uses for all build output and intermediate files (other than the 8981 shared state cache). By default, the :term:`TMPDIR` variable points to 8982 ``tmp`` within the :term:`Build Directory`. 8983 8984 If you want to establish this directory in a location other than the 8985 default, you can uncomment and edit the following statement in the 8986 ``conf/local.conf`` file in the :term:`Source Directory`:: 8987 8988 #TMPDIR = "${TOPDIR}/tmp" 8989 8990 An example use for this scenario is to set :term:`TMPDIR` to a local disk, 8991 which does not use NFS, while having the :term:`Build Directory` use NFS. 8992 8993 The filesystem used by :term:`TMPDIR` must have standard filesystem 8994 semantics (i.e. mixed-case files are unique, POSIX file locking, and 8995 persistent inodes). Due to various issues with NFS and bugs in some 8996 implementations, NFS does not meet this minimum requirement. 8997 Consequently, :term:`TMPDIR` cannot be on NFS. 8998 8999 :term:`TOOLCHAIN_HOST_TASK` 9000 This variable lists packages the OpenEmbedded build system uses when 9001 building an SDK, which contains a cross-development environment. The 9002 packages specified by this variable are part of the toolchain set 9003 that runs on the :term:`SDKMACHINE`, and each 9004 package should usually have the prefix ``nativesdk-``. For example, 9005 consider the following command when building an SDK:: 9006 9007 $ bitbake -c populate_sdk imagename 9008 9009 In this case, a default list of packages is 9010 set in this variable, but you can add additional packages to the 9011 list. See the 9012 ":ref:`sdk-manual/appendix-customizing-standard:adding individual packages to the standard sdk`" section 9013 in the Yocto Project Application Development and the Extensible 9014 Software Development Kit (eSDK) manual for more information. 9015 9016 For background information on cross-development toolchains in the 9017 Yocto Project development environment, see the 9018 ":ref:`sdk-manual/intro:the cross-development toolchain`" 9019 section in the Yocto Project Overview and Concepts Manual. For 9020 information on setting up a cross-development environment, see the 9021 :doc:`/sdk-manual/index` manual. 9022 9023 Note that this variable applies to building an SDK, not an eSDK, 9024 in which case the :term:`TOOLCHAIN_HOST_TASK_ESDK` setting should be 9025 used instead. 9026 9027 :term:`TOOLCHAIN_HOST_TASK_ESDK` 9028 This variable allows to extend what is installed in the host 9029 portion of an eSDK. This is similar to :term:`TOOLCHAIN_HOST_TASK` 9030 applying to SDKs. 9031 9032 :term:`TOOLCHAIN_OUTPUTNAME` 9033 This variable defines the name used for the toolchain output. The 9034 :ref:`populate_sdk_base <ref-classes-populate-sdk-*>` class sets 9035 the :term:`TOOLCHAIN_OUTPUTNAME` variable as follows:: 9036 9037 TOOLCHAIN_OUTPUTNAME ?= "${SDK_NAME}-toolchain-${SDK_VERSION}" 9038 9039 See 9040 the :term:`SDK_NAME` and 9041 :term:`SDK_VERSION` variables for additional 9042 information. 9043 9044 :term:`TOOLCHAIN_TARGET_TASK` 9045 This variable lists packages the OpenEmbedded build system uses when 9046 it creates the target part of an SDK (i.e. the part built for the 9047 target hardware), which includes libraries and headers. Use this 9048 variable to add individual packages to the part of the SDK that runs 9049 on the target. See the 9050 ":ref:`sdk-manual/appendix-customizing-standard:adding individual packages to the standard sdk`" section 9051 in the Yocto Project Application Development and the Extensible 9052 Software Development Kit (eSDK) manual for more information. 9053 9054 For background information on cross-development toolchains in the 9055 Yocto Project development environment, see the 9056 ":ref:`sdk-manual/intro:the cross-development toolchain`" 9057 section in the Yocto Project Overview and Concepts Manual. For 9058 information on setting up a cross-development environment, see the 9059 :doc:`/sdk-manual/index` manual. 9060 9061 :term:`TOPDIR` 9062 See :term:`bitbake:TOPDIR` in the BitBake manual. 9063 9064 :term:`TRANSLATED_TARGET_ARCH` 9065 A sanitized version of :term:`TARGET_ARCH`. This 9066 variable is used where the architecture is needed in a value where 9067 underscores are not allowed, for example within package filenames. In 9068 this case, dash characters replace any underscore characters used in 9069 :term:`TARGET_ARCH`. 9070 9071 Do not edit this variable. 9072 9073 :term:`TUNE_ARCH` 9074 The GNU canonical architecture for a specific architecture (i.e. 9075 ``arm``, ``armeb``, ``mips``, ``mips64``, and so forth). BitBake uses 9076 this value to setup configuration. 9077 9078 :term:`TUNE_ARCH` definitions are specific to a given architecture. The 9079 definitions can be a single static definition, or can be dynamically 9080 adjusted. You can see details for a given CPU family by looking at 9081 the architecture's ``README`` file. For example, the 9082 ``meta/conf/machine/include/mips/README`` file in the 9083 :term:`Source Directory` provides information for 9084 :term:`TUNE_ARCH` specific to the ``mips`` architecture. 9085 9086 :term:`TUNE_ARCH` is tied closely to 9087 :term:`TARGET_ARCH`, which defines the target 9088 machine's architecture. The BitBake configuration file 9089 (``meta/conf/bitbake.conf``) sets :term:`TARGET_ARCH` as follows:: 9090 9091 TARGET_ARCH = "${TUNE_ARCH}" 9092 9093 The following list, which is by no means complete since architectures 9094 are configurable, shows supported machine architectures: 9095 9096 - arm 9097 - i586 9098 - x86_64 9099 - powerpc 9100 - powerpc64 9101 - mips 9102 - mipsel 9103 9104 :term:`TUNE_ASARGS` 9105 Specifies architecture-specific assembler flags for the target 9106 system. The set of flags is based on the selected tune features. 9107 :term:`TUNE_ASARGS` is set using the tune include files, which are 9108 typically under ``meta/conf/machine/include/`` and are influenced 9109 through :term:`TUNE_FEATURES`. For example, the 9110 ``meta/conf/machine/include/x86/arch-x86.inc`` file defines the flags 9111 for the x86 architecture as follows:: 9112 9113 TUNE_ASARGS += "${@bb.utils.contains("TUNE_FEATURES", "mx32", "-x32", "", d)}" 9114 9115 .. note:: 9116 9117 Board Support Packages (BSPs) select the tune. The selected tune, 9118 in turn, affects the tune variables themselves (i.e. the tune can 9119 supply its own set of flags). 9120 9121 :term:`TUNE_CCARGS` 9122 Specifies architecture-specific C compiler flags for the target 9123 system. The set of flags is based on the selected tune features. 9124 :term:`TUNE_CCARGS` is set using the tune include files, which are 9125 typically under ``meta/conf/machine/include/`` and are influenced 9126 through :term:`TUNE_FEATURES`. 9127 9128 .. note:: 9129 9130 Board Support Packages (BSPs) select the tune. The selected tune, 9131 in turn, affects the tune variables themselves (i.e. the tune can 9132 supply its own set of flags). 9133 9134 :term:`TUNE_FEATURES` 9135 Features used to "tune" a compiler for optimal use given a specific 9136 processor. The features are defined within the tune files and allow 9137 arguments (i.e. ``TUNE_*ARGS``) to be dynamically generated based on 9138 the features. 9139 9140 The OpenEmbedded build system verifies the features to be sure they 9141 are not conflicting and that they are supported. 9142 9143 The BitBake configuration file (``meta/conf/bitbake.conf``) defines 9144 :term:`TUNE_FEATURES` as follows:: 9145 9146 TUNE_FEATURES ??= "${TUNE_FEATURES:tune-${DEFAULTTUNE}}" 9147 9148 See the :term:`DEFAULTTUNE` variable for more information. 9149 9150 :term:`TUNE_LDARGS` 9151 Specifies architecture-specific linker flags for the target system. 9152 The set of flags is based on the selected tune features. 9153 :term:`TUNE_LDARGS` is set using the tune include files, which are 9154 typically under ``meta/conf/machine/include/`` and are influenced 9155 through :term:`TUNE_FEATURES`. For example, the 9156 ``meta/conf/machine/include/x86/arch-x86.inc`` file defines the flags 9157 for the x86 architecture as follows:: 9158 9159 TUNE_LDARGS += "${@bb.utils.contains("TUNE_FEATURES", "mx32", "-m elf32_x86_64", "", d)}" 9160 9161 .. note:: 9162 9163 Board Support Packages (BSPs) select the tune. The selected tune, 9164 in turn, affects the tune variables themselves (i.e. the tune can 9165 supply its own set of flags). 9166 9167 :term:`TUNE_PKGARCH` 9168 The package architecture understood by the packaging system to define 9169 the architecture, ABI, and tuning of output packages. The specific 9170 tune is defined using the "_tune" override as follows:: 9171 9172 TUNE_PKGARCH:tune-tune = "tune" 9173 9174 These tune-specific package architectures are defined in the machine 9175 include files. Here is an example of the "core2-32" tuning as used in 9176 the ``meta/conf/machine/include/x86/tune-core2.inc`` file:: 9177 9178 TUNE_PKGARCH:tune-core2-32 = "core2-32" 9179 9180 :term:`TUNECONFLICTS[feature]` 9181 Specifies CPU or Application Binary Interface (ABI) tuning features 9182 that conflict with feature. 9183 9184 Known tuning conflicts are specified in the machine include files in 9185 the :term:`Source Directory`. Here is an example from 9186 the ``meta/conf/machine/include/mips/arch-mips.inc`` include file 9187 that lists the "o32" and "n64" features as conflicting with the "n32" 9188 feature:: 9189 9190 TUNECONFLICTS[n32] = "o32 n64" 9191 9192 :term:`TUNEVALID[feature]` 9193 Specifies a valid CPU or Application Binary Interface (ABI) tuning 9194 feature. The specified feature is stored as a flag. Valid features 9195 are specified in the machine include files (e.g. 9196 ``meta/conf/machine/include/arm/arch-arm.inc``). Here is an example 9197 from that file:: 9198 9199 TUNEVALID[bigendian] = "Enable big-endian mode." 9200 9201 See the machine include files in the :term:`Source Directory` 9202 for these features. 9203 9204 :term:`UBOOT_CONFIG` 9205 Configures the :term:`UBOOT_MACHINE` and can 9206 also define :term:`IMAGE_FSTYPES` for individual 9207 cases. 9208 9209 Following is an example from the ``meta-fsl-arm`` layer. :: 9210 9211 UBOOT_CONFIG ??= "sd" 9212 UBOOT_CONFIG[sd] = "mx6qsabreauto_config,sdcard" 9213 UBOOT_CONFIG[eimnor] = "mx6qsabreauto_eimnor_config" 9214 UBOOT_CONFIG[nand] = "mx6qsabreauto_nand_config,ubifs" 9215 UBOOT_CONFIG[spinor] = "mx6qsabreauto_spinor_config" 9216 9217 In this example, "sd" is selected as the configuration of the possible four for the 9218 :term:`UBOOT_MACHINE`. The "sd" configuration defines 9219 "mx6qsabreauto_config" as the value for :term:`UBOOT_MACHINE`, while the 9220 "sdcard" specifies the :term:`IMAGE_FSTYPES` to use for the U-Boot image. 9221 9222 For more information on how the :term:`UBOOT_CONFIG` is handled, see the 9223 :ref:`ref-classes-uboot-config` class. 9224 9225 :term:`UBOOT_DTB_LOADADDRESS` 9226 Specifies the load address for the dtb image used by U-Boot. During FIT 9227 image creation, the :term:`UBOOT_DTB_LOADADDRESS` variable is used in 9228 :ref:`ref-classes-kernel-fitimage` class to specify the load address to be 9229 used in creating the dtb sections of Image Tree Source for the FIT image. 9230 9231 :term:`UBOOT_DTBO_LOADADDRESS` 9232 Specifies the load address for the dtbo image used by U-Boot. During FIT 9233 image creation, the :term:`UBOOT_DTBO_LOADADDRESS` variable is used in 9234 :ref:`ref-classes-kernel-fitimage` class to specify the load address to be 9235 used in creating the dtbo sections of Image Tree Source for the FIT image. 9236 9237 :term:`UBOOT_ENTRYPOINT` 9238 Specifies the entry point for the U-Boot image. During U-Boot image 9239 creation, the :term:`UBOOT_ENTRYPOINT` variable is passed as a 9240 command-line parameter to the ``uboot-mkimage`` utility. 9241 9242 To pass a 64 bit address for FIT image creation, you will need to set: 9243 - The :term:`FIT_ADDRESS_CELLS` variable for FIT image creation. 9244 - The :term:`UBOOT_FIT_ADDRESS_CELLS` variable for U-Boot FIT image creation. 9245 9246 This variable is used by the :ref:`ref-classes-kernel-fitimage`, 9247 :ref:`ref-classes-kernel-uimage`, :ref:`ref-classes-kernel`, 9248 :ref:`ref-classes-uboot-config` and :ref:`ref-classes-uboot-sign` 9249 classes. 9250 9251 :term:`UBOOT_FIT_ADDRESS_CELLS` 9252 Specifies the value of the ``#address-cells`` value for the 9253 description of the U-Boot FIT image. 9254 9255 The default value is set to "1" by the :ref:`ref-classes-uboot-sign` 9256 class, which corresponds to 32 bit addresses. 9257 9258 For platforms that need to set 64 bit addresses in 9259 :term:`UBOOT_LOADADDRESS` and :term:`UBOOT_ENTRYPOINT`, you need to 9260 set this value to "2", as two 32 bit values (cells) will be needed 9261 to represent such addresses. 9262 9263 Here is an example setting "0x400000000" as a load address:: 9264 9265 UBOOT_FIT_ADDRESS_CELLS = "2" 9266 UBOOT_LOADADDRESS= "0x04 0x00000000" 9267 9268 See `more details about #address-cells <https://elinux.org/Device_Tree_Usage#How_Addressing_Works>`__. 9269 9270 :term:`UBOOT_FIT_DESC` 9271 Specifies the description string encoded into a U-Boot fitImage. The default 9272 value is set by the :ref:`ref-classes-uboot-sign` class as follows:: 9273 9274 UBOOT_FIT_DESC ?= "U-Boot fitImage for ${DISTRO_NAME}/${PV}/${MACHINE}" 9275 9276 :term:`UBOOT_FIT_GENERATE_KEYS` 9277 Decides whether to generate the keys for signing the U-Boot fitImage if 9278 they don't already exist. The keys are created in :term:`SPL_SIGN_KEYDIR`. 9279 The default value is "0". 9280 9281 Enable this as follows:: 9282 9283 UBOOT_FIT_GENERATE_KEYS = "1" 9284 9285 This variable is used in the :ref:`ref-classes-uboot-sign` class. 9286 9287 :term:`UBOOT_FIT_HASH_ALG` 9288 Specifies the hash algorithm used in creating the U-Boot FIT Image. 9289 It is set by default to ``sha256`` by the :ref:`ref-classes-uboot-sign` 9290 class. 9291 9292 :term:`UBOOT_FIT_KEY_GENRSA_ARGS` 9293 Arguments to ``openssl genrsa`` for generating a RSA private key for 9294 signing the U-Boot FIT image. The default value of this variable 9295 is set to "-F4" by the :ref:`ref-classes-uboot-sign` class. 9296 9297 :term:`UBOOT_FIT_KEY_REQ_ARGS` 9298 Arguments to ``openssl req`` for generating a certificate for signing 9299 the U-Boot FIT image. The default value is "-batch -new" by the 9300 :ref:`ref-classes-uboot-sign` class, "batch" for 9301 non interactive mode and "new" for generating new keys. 9302 9303 :term:`UBOOT_FIT_KEY_SIGN_PKCS` 9304 Format for the public key certificate used for signing the U-Boot FIT 9305 image. The default value is set to "x509" by the 9306 :ref:`ref-classes-uboot-sign` class. 9307 9308 :term:`UBOOT_FIT_SIGN_ALG` 9309 Specifies the signature algorithm used in creating the U-Boot FIT Image. 9310 This variable is set by default to "rsa2048" by the 9311 :ref:`ref-classes-uboot-sign` class. 9312 9313 :term:`UBOOT_FIT_SIGN_NUMBITS` 9314 Size of the private key used in signing the U-Boot FIT image, in number 9315 of bits. The default value for this variable is set to "2048" 9316 by the :ref:`ref-classes-uboot-sign` class. 9317 9318 :term:`UBOOT_FITIMAGE_ENABLE` 9319 This variable allows to generate a FIT image for U-Boot, which is one 9320 of the ways to implement a verified boot process. 9321 9322 Its default value is "0", so set it to "1" to enable this functionality:: 9323 9324 UBOOT_FITIMAGE_ENABLE = "1" 9325 9326 See the :ref:`ref-classes-uboot-sign` class for details. 9327 9328 :term:`UBOOT_LOADADDRESS` 9329 Specifies the load address for the U-Boot image. During U-Boot image 9330 creation, the :term:`UBOOT_LOADADDRESS` variable is passed as a 9331 command-line parameter to the ``uboot-mkimage`` utility. 9332 9333 To pass a 64 bit address, you will also need to set: 9334 9335 - The :term:`FIT_ADDRESS_CELLS` variable for FIT image creation. 9336 - The :term:`UBOOT_FIT_ADDRESS_CELLS` variable for U-Boot FIT image creation. 9337 9338 This variable is used by the :ref:`ref-classes-kernel-fitimage`, 9339 :ref:`ref-classes-kernel-uimage`, :ref:`ref-classes-kernel`, 9340 :ref:`ref-classes-uboot-config` and :ref:`ref-classes-uboot-sign` 9341 classes. 9342 9343 :term:`UBOOT_LOCALVERSION` 9344 Appends a string to the name of the local version of the U-Boot 9345 image. For example, assuming the version of the U-Boot image built 9346 was "2013.10", the full version string reported by U-Boot would be 9347 "2013.10-yocto" given the following statement:: 9348 9349 UBOOT_LOCALVERSION = "-yocto" 9350 9351 :term:`UBOOT_MACHINE` 9352 Specifies the value passed on the ``make`` command line when building 9353 a U-Boot image. The value indicates the target platform 9354 configuration. You typically set this variable from the machine 9355 configuration file (i.e. ``conf/machine/machine_name.conf``). 9356 9357 Please see the "Selection of Processor Architecture and Board Type" 9358 section in the U-Boot README for valid values for this variable. 9359 9360 :term:`UBOOT_MAKE_TARGET` 9361 Specifies the target called in the ``Makefile``. The default target 9362 is "all". 9363 9364 :term:`UBOOT_MKIMAGE` 9365 Specifies the name of the mkimage command as used by the 9366 :ref:`ref-classes-kernel-fitimage` class to assemble 9367 the FIT image. This can be used to substitute an alternative command, wrapper 9368 script or function if desired. The default is "uboot-mkimage". 9369 9370 :term:`UBOOT_MKIMAGE_DTCOPTS` 9371 Options for the device tree compiler passed to ``mkimage -D`` feature 9372 while creating a FIT image with the :ref:`ref-classes-kernel-fitimage` 9373 class. If :term:`UBOOT_MKIMAGE_DTCOPTS` is not set then the 9374 :ref:`ref-classes-kernel-fitimage` class will not pass the ``-D`` option 9375 to ``mkimage``. 9376 9377 This variable is also used by the :ref:`ref-classes-uboot-sign` class. 9378 9379 :term:`UBOOT_MKIMAGE_KERNEL_TYPE` 9380 Specifies the type argument for the kernel as passed to ``uboot-mkimage``. 9381 The default value is "kernel". 9382 9383 :term:`UBOOT_MKIMAGE_SIGN` 9384 Specifies the name of the mkimage command as used by the 9385 :ref:`ref-classes-kernel-fitimage` class to sign 9386 the FIT image after it has been assembled (if enabled). This can be used 9387 to substitute an alternative command, wrapper script or function if 9388 desired. The default is "${:term:`UBOOT_MKIMAGE`}". 9389 9390 :term:`UBOOT_MKIMAGE_SIGN_ARGS` 9391 Optionally specifies additional arguments for the 9392 :ref:`ref-classes-kernel-fitimage` class to pass to the 9393 mkimage command when signing the FIT image. 9394 9395 :term:`UBOOT_RD_ENTRYPOINT` 9396 Specifies the entrypoint for the RAM disk image. During FIT image 9397 creation, the :term:`UBOOT_RD_ENTRYPOINT` variable is used in 9398 :ref:`ref-classes-kernel-fitimage` class to specify the entrypoint to be 9399 used in creating the Image Tree Source for the FIT image. 9400 9401 :term:`UBOOT_RD_LOADADDRESS` 9402 Specifies the load address for the RAM disk image. During FIT image 9403 creation, the :term:`UBOOT_RD_LOADADDRESS` variable is used in 9404 :ref:`ref-classes-kernel-fitimage` class to specify the load address to 9405 be used in creating the Image Tree Source for the FIT image. 9406 9407 :term:`UBOOT_SIGN_ENABLE` 9408 Enable signing of FIT image. The default value is "0". 9409 9410 This variable is used by the :ref:`ref-classes-kernel-fitimage`, 9411 :ref:`ref-classes-uboot-config` and :ref:`ref-classes-uboot-sign` 9412 classes. 9413 9414 :term:`UBOOT_SIGN_KEYDIR` 9415 Location of the directory containing the RSA key and certificate used for 9416 signing FIT image, used by the :ref:`ref-classes-kernel-fitimage` and 9417 :ref:`ref-classes-uboot-sign` classes. 9418 9419 :term:`UBOOT_SIGN_KEYNAME` 9420 The name of keys used by the :ref:`ref-classes-kernel-fitimage` class 9421 for signing U-Boot FIT image stored in the :term:`UBOOT_SIGN_KEYDIR` 9422 directory. If we have for example a ``dev.key`` key and a ``dev.crt`` 9423 certificate stored in the :term:`UBOOT_SIGN_KEYDIR` directory, you will 9424 have to set :term:`UBOOT_SIGN_KEYNAME` to ``dev``. 9425 9426 :term:`UBOOT_SUFFIX` 9427 Points to the generated U-Boot extension. For example, ``u-boot.sb`` 9428 has a ``.sb`` extension. 9429 9430 The default U-Boot extension is ``.bin`` 9431 9432 :term:`UBOOT_TARGET` 9433 Specifies the target used for building U-Boot. The target is passed 9434 directly as part of the "make" command (e.g. SPL and AIS). If you do 9435 not specifically set this variable, the OpenEmbedded build process 9436 passes and uses "all" for the target during the U-Boot building 9437 process. 9438 9439 :term:`UNKNOWN_CONFIGURE_OPT_IGNORE` 9440 Specifies a list of options that, if reported by the configure script 9441 as being invalid, should not generate a warning during the 9442 :ref:`ref-tasks-configure` task. Normally, invalid 9443 configure options are simply not passed to the configure script (e.g. 9444 should be removed from :term:`EXTRA_OECONF` or 9445 :term:`PACKAGECONFIG_CONFARGS`). 9446 However, there are common options that are passed to all 9447 configure scripts at a class level, but might not be valid for some 9448 configure scripts. Therefore warnings about these options are useless. 9449 For these cases, the options are added to :term:`UNKNOWN_CONFIGURE_OPT_IGNORE`. 9450 9451 The configure arguments check that uses 9452 :term:`UNKNOWN_CONFIGURE_OPT_IGNORE` is part of the 9453 :ref:`ref-classes-insane` class and is only enabled if the 9454 recipe inherits the :ref:`ref-classes-autotools` class. 9455 9456 :term:`UPDATERCPN` 9457 For recipes inheriting the 9458 :ref:`ref-classes-update-rc.d` class, :term:`UPDATERCPN` 9459 specifies the package that contains the initscript that is enabled. 9460 9461 The default value is "${PN}". Given that almost all recipes that 9462 install initscripts package them in the main package for the recipe, 9463 you rarely need to set this variable in individual recipes. 9464 9465 :term:`UPSTREAM_CHECK_COMMITS` 9466 You can perform a per-recipe check for what the latest upstream 9467 source code version is by calling ``devtool latest-version recipe``. If 9468 the recipe source code is provided from Git repositories, but 9469 releases are not identified by Git tags, set :term:`UPSTREAM_CHECK_COMMITS` 9470 to ``1`` in the recipe, and the OpenEmbedded build system 9471 will compare the latest commit with the one currently specified 9472 by the recipe (:term:`SRCREV`):: 9473 9474 UPSTREAM_CHECK_COMMITS = "1" 9475 9476 :term:`UPSTREAM_CHECK_GITTAGREGEX` 9477 You can perform a per-recipe check for what the latest upstream 9478 source code version is by calling ``devtool latest-version recipe``. If 9479 the recipe source code is provided from Git repositories, the 9480 OpenEmbedded build system determines the latest upstream version by 9481 picking the latest tag from the list of all repository tags. 9482 9483 You can use the :term:`UPSTREAM_CHECK_GITTAGREGEX` variable to provide a 9484 regular expression to filter only the relevant tags should the 9485 default filter not work correctly:: 9486 9487 UPSTREAM_CHECK_GITTAGREGEX = "git_tag_regex" 9488 9489 :term:`UPSTREAM_CHECK_REGEX` 9490 Use the :term:`UPSTREAM_CHECK_REGEX` variable to specify a different 9491 regular expression instead of the default one when the package 9492 checking system is parsing the page found using 9493 :term:`UPSTREAM_CHECK_URI`:: 9494 9495 UPSTREAM_CHECK_REGEX = "package_regex" 9496 9497 :term:`UPSTREAM_CHECK_URI` 9498 You can perform a per-recipe check for what the latest upstream 9499 source code version is by calling ``devtool latest-version recipe``. If 9500 the source code is provided from tarballs, the latest version is 9501 determined by fetching the directory listing where the tarball is and 9502 attempting to find a later tarball. When this approach does not work, 9503 you can use :term:`UPSTREAM_CHECK_URI` to provide a different URI that 9504 contains the link to the latest tarball:: 9505 9506 UPSTREAM_CHECK_URI = "recipe_url" 9507 9508 :term:`UPSTREAM_VERSION_UNKNOWN` 9509 You can perform a per-recipe check for what the latest upstream 9510 source code version is by calling ``devtool latest-version recipe``. 9511 If no combination of the :term:`UPSTREAM_CHECK_URI`, :term:`UPSTREAM_CHECK_REGEX`, 9512 :term:`UPSTREAM_CHECK_GITTAGREGEX` and :term:`UPSTREAM_CHECK_COMMITS` variables in 9513 the recipe allows to determine what the latest upstream version is, 9514 you can set :term:`UPSTREAM_VERSION_UNKNOWN` to ``1`` in the recipe 9515 to acknowledge that the check cannot be performed:: 9516 9517 UPSTREAM_VERSION_UNKNOWN = "1" 9518 9519 :term:`USE_DEVFS` 9520 Determines if ``devtmpfs`` is used for ``/dev`` population. The 9521 default value used for :term:`USE_DEVFS` is "1" when no value is 9522 specifically set. Typically, you would set :term:`USE_DEVFS` to "0" for a 9523 statically populated ``/dev`` directory. 9524 9525 See the ":ref:`dev-manual/device-manager:selecting a device manager`" section in 9526 the Yocto Project Development Tasks Manual for information on how to 9527 use this variable. 9528 9529 :term:`USE_VT` 9530 When using 9531 :ref:`SysVinit <dev-manual/new-recipe:enabling system services>`, 9532 determines whether or not to run a :wikipedia:`getty <Getty_(Unix)>` 9533 on any virtual terminals in order to enable logging in through those 9534 terminals. 9535 9536 The default value used for :term:`USE_VT` is "1" when no default value is 9537 specifically set. Typically, you would set :term:`USE_VT` to "0" in the 9538 machine configuration file for machines that do not have a graphical 9539 display attached and therefore do not need virtual terminal 9540 functionality. 9541 9542 :term:`USER_CLASSES` 9543 A list of classes to globally inherit. These classes are used by the 9544 OpenEmbedded build system to enable extra features. 9545 9546 Classes inherited using :term:`USER_CLASSES` must be located in the 9547 ``classes-global/`` or ``classes/`` subdirectories. 9548 9549 The default list is set in your ``local.conf`` file:: 9550 9551 USER_CLASSES ?= "buildstats" 9552 9553 For more information, see 9554 ``meta-poky/conf/templates/default/local.conf.sample`` in the 9555 :term:`Source Directory`. 9556 9557 :term:`USERADD_ERROR_DYNAMIC` 9558 If set to ``error``, forces the OpenEmbedded build system to produce 9559 an error if the user identification (``uid``) and group 9560 identification (``gid``) values are not defined in any of the files 9561 listed in :term:`USERADD_UID_TABLES` and 9562 :term:`USERADD_GID_TABLES`. If set to 9563 ``warn``, a warning will be issued instead. 9564 9565 The default behavior for the build system is to dynamically apply 9566 ``uid`` and ``gid`` values. Consequently, the 9567 :term:`USERADD_ERROR_DYNAMIC` variable is by default not set. If you plan 9568 on using statically assigned ``gid`` and ``uid`` values, you should 9569 set the :term:`USERADD_ERROR_DYNAMIC` variable in your ``local.conf`` 9570 file as follows:: 9571 9572 USERADD_ERROR_DYNAMIC = "error" 9573 9574 Overriding the 9575 default behavior implies you are going to also take steps to set 9576 static ``uid`` and ``gid`` values through use of the 9577 :term:`USERADDEXTENSION`, 9578 :term:`USERADD_UID_TABLES`, and 9579 :term:`USERADD_GID_TABLES` variables. 9580 9581 .. note:: 9582 9583 There is a difference in behavior between setting 9584 :term:`USERADD_ERROR_DYNAMIC` to ``error`` and setting it to ``warn``. 9585 When it is set to ``warn``, the build system will report a warning for 9586 every undefined ``uid`` and ``gid`` in any recipe. But when it is set 9587 to ``error``, it will only report errors for recipes that are actually 9588 built. 9589 This saves you from having to add static IDs for recipes that you 9590 know will never be built. 9591 9592 :term:`USERADD_GID_TABLES` 9593 Specifies a password file to use for obtaining static group 9594 identification (``gid``) values when the OpenEmbedded build system 9595 adds a group to the system during package installation. 9596 9597 When applying static group identification (``gid``) values, the 9598 OpenEmbedded build system looks in :term:`BBPATH` for a 9599 ``files/group`` file and then applies those ``uid`` values. Set the 9600 variable as follows in your ``local.conf`` file:: 9601 9602 9603 USERADD_GID_TABLES = "files/group" 9604 9605 .. note:: 9606 9607 Setting the :term:`USERADDEXTENSION` variable to "useradd-staticids" 9608 causes the build system to use static ``gid`` values. 9609 9610 :term:`USERADD_PACKAGES` 9611 When inheriting the :ref:`ref-classes-useradd` class, 9612 this variable specifies the individual packages within the recipe 9613 that require users and/or groups to be added. 9614 9615 You must set this variable if the recipe inherits the class. For 9616 example, the following enables adding a user for the main package in 9617 a recipe:: 9618 9619 USERADD_PACKAGES = "${PN}" 9620 9621 .. note:: 9622 9623 It follows that if you are going to use the :term:`USERADD_PACKAGES` 9624 variable, you need to set one or more of the :term:`USERADD_PARAM`, 9625 :term:`GROUPADD_PARAM`, or :term:`GROUPMEMS_PARAM` variables. 9626 9627 :term:`USERADD_PARAM` 9628 When inheriting the :ref:`ref-classes-useradd` class, 9629 this variable specifies for a package what parameters should pass to 9630 the ``useradd`` command if you add a user to the system when the 9631 package is installed. 9632 9633 Here is an example from the ``dbus`` recipe:: 9634 9635 USERADD_PARAM:${PN} = "--system --home ${localstatedir}/lib/dbus \ 9636 --no-create-home --shell /bin/false \ 9637 --user-group messagebus" 9638 9639 For information on the 9640 standard Linux shell command ``useradd``, see 9641 https://linux.die.net/man/8/useradd. 9642 9643 :term:`USERADD_UID_TABLES` 9644 Specifies a password file to use for obtaining static user 9645 identification (``uid``) values when the OpenEmbedded build system 9646 adds a user to the system during package installation. 9647 9648 When applying static user identification (``uid``) values, the 9649 OpenEmbedded build system looks in :term:`BBPATH` for a 9650 ``files/passwd`` file and then applies those ``uid`` values. Set the 9651 variable as follows in your ``local.conf`` file:: 9652 9653 USERADD_UID_TABLES = "files/passwd" 9654 9655 .. note:: 9656 9657 Setting the :term:`USERADDEXTENSION` variable to "useradd-staticids" 9658 causes the build system to use static ``uid`` values. 9659 9660 :term:`USERADDEXTENSION` 9661 When set to "useradd-staticids", causes the OpenEmbedded build system 9662 to base all user and group additions on a static ``passwd`` and 9663 ``group`` files found in :term:`BBPATH`. 9664 9665 To use static user identification (``uid``) and group identification 9666 (``gid``) values, set the variable as follows in your ``local.conf`` 9667 file: USERADDEXTENSION = "useradd-staticids" 9668 9669 .. note:: 9670 9671 Setting this variable to use static ``uid`` and ``gid`` 9672 values causes the OpenEmbedded build system to employ the 9673 :ref:`ref-classes-useradd` class. 9674 9675 If you use static ``uid`` and ``gid`` information, you must also 9676 specify the ``files/passwd`` and ``files/group`` files by setting the 9677 :term:`USERADD_UID_TABLES` and 9678 :term:`USERADD_GID_TABLES` variables. 9679 Additionally, you should also set the 9680 :term:`USERADD_ERROR_DYNAMIC` variable. 9681 9682 :term:`VOLATILE_LOG_DIR` 9683 Specifies the persistence of the target's ``/var/log`` directory, 9684 which is used to house postinstall target log files. 9685 9686 By default, :term:`VOLATILE_LOG_DIR` is set to "yes", which means the 9687 file is not persistent. You can override this setting by setting the 9688 variable to "no" to make the log directory persistent. 9689 9690 :term:`VOLATILE_TMP_DIR` 9691 Specifies the persistence of the target's ``/tmp`` directory. 9692 9693 By default, :term:`VOLATILE_TMP_DIR` is set to "yes", in which case 9694 ``/tmp`` links to a directory which resides in RAM in a ``tmpfs`` 9695 filesystem. 9696 9697 If instead, you want the ``/tmp`` directory to be persistent, set the 9698 variable to "no" to make it a regular directory in the root filesystem. 9699 9700 This supports both sysvinit and systemd based systems. 9701 9702 :term:`WARN_QA` 9703 Specifies the quality assurance checks whose failures are reported as 9704 warnings by the OpenEmbedded build system. You set this variable in 9705 your distribution configuration file. For a list of the checks you 9706 can control with this variable, see the 9707 ":ref:`ref-classes-insane`" section. 9708 9709 :term:`WATCHDOG_TIMEOUT` 9710 Specifies the timeout in seconds used by the ``watchdog`` recipe and 9711 also by ``systemd`` during reboot. The default is 60 seconds. 9712 9713 :term:`WIRELESS_DAEMON` 9714 For ``connman`` and ``packagegroup-base``, specifies the wireless 9715 daemon to use. The default is "wpa-supplicant" (note that the value 9716 uses a dash and not an underscore). 9717 9718 :term:`WKS_FILE` 9719 Specifies the location of the Wic kickstart file that is used by the 9720 OpenEmbedded build system to create a partitioned image 9721 (``image.wic``). For information on how to create a partitioned 9722 image, see the 9723 ":ref:`dev-manual/wic:creating partitioned images using wic`" 9724 section in the Yocto Project Development Tasks Manual. For details on 9725 the kickstart file format, see the ":doc:`/ref-manual/kickstart`" Chapter. 9726 9727 :term:`WKS_FILE_DEPENDS` 9728 When placed in the recipe that builds your image, this variable lists 9729 build-time dependencies. The :term:`WKS_FILE_DEPENDS` variable is only 9730 applicable when Wic images are active (i.e. when 9731 :term:`IMAGE_FSTYPES` contains entries related 9732 to Wic). If your recipe does not create Wic images, the variable has 9733 no effect. 9734 9735 The :term:`WKS_FILE_DEPENDS` variable is similar to the 9736 :term:`DEPENDS` variable. When you use the variable in 9737 your recipe that builds the Wic image, dependencies you list in the 9738 :term:`WKS_FILE_DEPENDS` variable are added to the :term:`DEPENDS` variable. 9739 9740 With the :term:`WKS_FILE_DEPENDS` variable, you have the possibility to 9741 specify a list of additional dependencies (e.g. native tools, 9742 bootloaders, and so forth), that are required to build Wic images. 9743 Following is an example:: 9744 9745 WKS_FILE_DEPENDS = "some-native-tool" 9746 9747 In the 9748 previous example, some-native-tool would be replaced with an actual 9749 native tool on which the build would depend. 9750 9751 :term:`WKS_FILES` 9752 Specifies a list of candidate Wic kickstart files to be used by the 9753 OpenEmbedded build system to create a partitioned image. Only the 9754 first one that is found, from left to right, will be used. 9755 9756 This is only useful when there are multiple ``.wks`` files that can be 9757 used to produce an image. A typical case is when multiple layers are 9758 used for different hardware platforms, each supplying a different 9759 ``.wks`` file. In this case, you specify all possible ones through 9760 :term:`WKS_FILES`. 9761 9762 If only one ``.wks`` file is used, set :term:`WKS_FILE` instead. 9763 9764 :term:`WORKDIR` 9765 The pathname of the work directory in which the OpenEmbedded build 9766 system builds a recipe. This directory is located within the 9767 :term:`TMPDIR` directory structure and is specific to 9768 the recipe being built and the system for which it is being built. 9769 9770 The :term:`WORKDIR` directory is defined as follows:: 9771 9772 ${TMPDIR}/work/${MULTIMACH_TARGET_SYS}/${PN}/${EXTENDPE}${PV}-${PR} 9773 9774 The actual directory depends on several things: 9775 9776 - :term:`TMPDIR`: The top-level build output directory 9777 - :term:`MULTIMACH_TARGET_SYS`: The target system identifier 9778 - :term:`PN`: The recipe name 9779 - :term:`EXTENDPE`: The epoch --- if :term:`PE` is not specified, which 9780 is usually the case for most recipes, then :term:`EXTENDPE` is blank. 9781 - :term:`PV`: The recipe version 9782 - :term:`PR`: The recipe revision 9783 9784 As an example, assume a Source Directory top-level folder name 9785 ``poky``, a default :term:`Build Directory` at ``poky/build``, and a 9786 ``qemux86-poky-linux`` machine target system. Furthermore, suppose 9787 your recipe is named ``foo_1.3.0-r0.bb``. In this case, the work 9788 directory the build system uses to build the package would be as 9789 follows:: 9790 9791 poky/build/tmp/work/qemux86-poky-linux/foo/1.3.0-r0 9792 9793 :term:`XSERVER` 9794 Specifies the packages that should be installed to provide an X 9795 server and drivers for the current machine, assuming your image 9796 directly includes ``packagegroup-core-x11-xserver`` or, perhaps 9797 indirectly, includes "x11-base" in 9798 :term:`IMAGE_FEATURES`. 9799 9800 The default value of :term:`XSERVER`, if not specified in the machine 9801 configuration, is "xserver-xorg xf86-video-fbdev xf86-input-evdev". 9802 9803 :term:`XZ_THREADS` 9804 Specifies the number of parallel threads that should be used when 9805 using xz compression. 9806 9807 By default this scales with core count, but is never set less than 2 9808 to ensure that multi-threaded mode is always used so that the output 9809 file contents are deterministic. Builds will work with a value of 1 9810 but the output will differ compared to the output from the compression 9811 generated when more than one thread is used. 9812 9813 On systems where many tasks run in parallel, setting a limit to this 9814 can be helpful in controlling system resource usage. 9815 9816 :term:`XZ_MEMLIMIT` 9817 Specifies the maximum memory the xz compression should use as a percentage 9818 of system memory. If unconstrained the xz compressor can use large amounts of 9819 memory and become problematic with parallelism elsewhere in the build. 9820 "50%" has been found to be a good value. 9821 9822 :term:`ZSTD_THREADS` 9823 Specifies the number of parallel threads that should be used when 9824 using ZStandard compression. 9825 9826 By default this scales with core count, but is never set less than 2 9827 to ensure that multi-threaded mode is always used so that the output 9828 file contents are deterministic. Builds will work with a value of 1 9829 but the output will differ compared to the output from the compression 9830 generated when more than one thread is used. 9831 9832 On systems where many tasks run in parallel, setting a limit to this 9833 can be helpful in controlling system resource usage. 9834
