1 2 GNU Free Documentation License 3 Version 1.2, November 2002 4 5 6 Copyright (C) 2000,2001,2002 Free Software Foundation, Inc. 7 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 8 Everyone is permitted to copy and distribute verbatim copies 9 of this license document, but changing it is not allowed. 10 11 120. PREAMBLE 13 14The purpose of this License is to make a manual, textbook, or other 15functional and useful document "free" in the sense of freedom: to 16assure everyone the effective freedom to copy and redistribute it, 17with or without modifying it, either commercially or noncommercially. 18Secondarily, this License preserves for the author and publisher a way 19to get credit for their work, while not being considered responsible 20for modifications made by others. 21 22This License is a kind of "copyleft", which means that derivative 23works of the document must themselves be free in the same sense. It 24complements the GNU General Public License, which is a copyleft 25license designed for free software. 26 27We have designed this License in order to use it for manuals for free 28software, because free software needs free documentation: a free 29program should come with manuals providing the same freedoms that the 30software does. But this License is not limited to software manuals; 31it can be used for any textual work, regardless of subject matter or 32whether it is published as a printed book. We recommend this License 33principally for works whose purpose is instruction or reference. 34 35 361. APPLICABILITY AND DEFINITIONS 37 38This License applies to any manual or other work, in any medium, that 39contains a notice placed by the copyright holder saying it can be 40distributed under the terms of this License. Such a notice grants a 41world-wide, royalty-free license, unlimited in duration, to use that 42work under the conditions stated herein. The "Document", below, 43refers to any such manual or work. Any member of the public is a 44licensee, and is addressed as "you". You accept the license if you 45copy, modify or distribute the work in a way requiring permission 46under copyright law. 47 48A "Modified Version" of the Document means any work containing the 49Document or a portion of it, either copied verbatim, or with 50modifications and/or translated into another language. 51 52A "Secondary Section" is a named appendix or a front-matter section of 53the Document that deals exclusively with the relationship of the 54publishers or authors of the Document to the Document`s overall subject 55(or to related matters) and contains nothing that could fall directly 56within that overall subject. (Thus, if the Document is in part a 57textbook of mathematics, a Secondary Section may not explain any 58mathematics.) The relationship could be a matter of historical 59connection with the subject or with related matters, or of legal, 60commercial, philosophical, ethical or political position regarding 61them. 62 63The "Invariant Sections" are certain Secondary Sections whose titles 64are designated, as being those of Invariant Sections, in the notice 65that says that the Document is released under this License. If a 66section does not fit the above definition of Secondary then it is not 67allowed to be designated as Invariant. The Document may contain zero 68Invariant Sections. If the Document does not identify any Invariant 69Sections then there are none. 70 71The "Cover Texts" are certain short passages of text that are listed, 72as Front-Cover Texts or Back-Cover Texts, in the notice that says that 73the Document is released under this License. A Front-Cover Text may 74be at most 5 words, and a Back-Cover Text may be at most 25 words. 75 76A "Transparent" copy of the Document means a machine-readable copy, 77represented in a format whose specification is available to the 78general public, that is suitable for revising the document 79straightforwardly with generic text editors or (for images composed of 80pixels) generic paint programs or (for drawings) some widely available 81drawing editor, and that is suitable for input to text formatters or 82for automatic translation to a variety of formats suitable for input 83to text formatters. A copy made in an otherwise Transparent file 84format whose markup, or absence of markup, has been arranged to thwart 85or discourage subsequent modification by readers is not Transparent. 86An image format is not Transparent if used for any substantial amount 87of text. A copy that is not "Transparent" is called "Opaque". 88 89Examples of suitable formats for Transparent copies include plain 90ASCII without markup, Texinfo input format, LaTeX input format, SGML 91or XML using a publicly available DTD, and standard-conforming simple 92HTML, PostScript or PDF designed for human modification. Examples of 93transparent image formats include PNG, XCF and JPG. Opaque formats 94include proprietary formats that can be read and edited only by 95proprietary word processors, SGML or XML for which the DTD and/or 96processing tools are not generally available, and the 97machine-generated HTML, PostScript or PDF produced by some word 98processors for output purposes only. 99 100The "Title Page" means, for a printed book, the title page itself, 101plus such following pages as are needed to hold, legibly, the material 102this License requires to appear in the title page. For works in 103formats which do not have any title page as such, "Title Page" means 104the text near the most prominent appearance of the work`s title, 105preceding the beginning of the body of the text. 106 107A section "Entitled XYZ" means a named subunit of the Document whose 108title either is precisely XYZ or contains XYZ in parentheses following 109text that translates XYZ in another language. (Here XYZ stands for a 110specific section name mentioned below, such as "Acknowledgements", 111"Dedications", "Endorsements", or "History".) To "Preserve the Title" 112of such a section when you modify the Document means that it remains a 113section "Entitled XYZ" according to this definition. 114 115The Document may include Warranty Disclaimers next to the notice which 116states that this License applies to the Document. These Warranty 117Disclaimers are considered to be included by reference in this 118License, but only as regards disclaiming warranties: any other 119implication that these Warranty Disclaimers may have is void and has 120no effect on the meaning of this License. 121 122 1232. VERBATIM COPYING 124 125You may copy and distribute the Document in any medium, either 126commercially or noncommercially, provided that this License, the 127copyright notices, and the license notice saying this License applies 128to the Document are reproduced in all copies, and that you add no other 129conditions whatsoever to those of this License. You may not use 130technical measures to obstruct or control the reading or further 131copying of the copies you make or distribute. However, you may accept 132compensation in exchange for copies. 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You may add other material on the covers in addition. 150Copying with changes limited to the covers, as long as they preserve 151the title of the Document and satisfy these conditions, can be treated 152as verbatim copying in other respects. 153 154If the required texts for either cover are too voluminous to fit 155legibly, you should put the first ones listed (as many as fit 156reasonably) on the actual cover, and continue the rest onto adjacent 157pages. 158 159If you publish or distribute Opaque copies of the Document numbering 160more than 100, you must either include a machine-readable Transparent 161copy along with each Opaque copy, or state in or with each Opaque copy 162a computer-network location from which the general network-using 163public has access to download using public-standard network protocols 164a complete Transparent copy of the Document, free of added material. 165If you use the latter option, you must take reasonably prudent steps, 166when you begin distribution of Opaque copies in quantity, to ensure 167that this Transparent copy will remain thus accessible at the stated 168location until at least one year after the last time you distribute an 169Opaque copy (directly or through your agents or retailers) of that 170edition to the public. 171 172It is requested, but not required, that you contact the authors of the 173Document well before redistributing any large number of copies, to give 174them a chance to provide you with an updated version of the Document. 175 176 1774. MODIFICATIONS 178 179You may copy and distribute a Modified Version of the Document under 180the conditions of sections 2 and 3 above, provided that you release 181the Modified Version under precisely this License, with the Modified 182Version filling the role of the Document, thus licensing distribution 183and modification of the Modified Version to whoever possesses a copy 184of it. In addition, you must do these things in the Modified Version: 185 186A. Use in the Title Page (and on the covers, if any) a title distinct 187 from that of the Document, and from those of previous versions 188 (which should, if there were any, be listed in the History section 189 of the Document). You may use the same title as a previous version 190 if the original publisher of that version gives permission. 191B. List on the Title Page, as authors, one or more persons or entities 192 responsible for authorship of the modifications in the Modified 193 Version, together with at least five of the principal authors of the 194 Document (all of its principal authors, if it has fewer than five), 195 unless they release you from this requirement. 196C. State on the Title page the name of the publisher of the 197 Modified Version, as the publisher. 198D. Preserve all the copyright notices of the Document. 199E. Add an appropriate copyright notice for your modifications 200 adjacent to the other copyright notices. 201F. Include, immediately after the copyright notices, a license notice 202 giving the public permission to use the Modified Version under the 203 terms of this License, in the form shown in the Addendum below. 204G. Preserve in that license notice the full lists of Invariant Sections 205 and required Cover Texts given in the Document`s license notice. 206H. Include an unaltered copy of this License. 207I. Preserve the section Entitled "History", Preserve its Title, and add 208 to it an item stating at least the title, year, new authors, and 209 publisher of the Modified Version as given on the Title Page. If 210 there is no section Entitled "History" in the Document, create one 211 stating the title, year, authors, and publisher of the Document as 212 given on its Title Page, then add an item describing the Modified 213 Version as stated in the previous sentence. 214J. Preserve the network location, if any, given in the Document for 215 public access to a Transparent copy of the Document, and likewise 216 the network locations given in the Document for previous versions 217 it was based on. These may be placed in the "History" section. 218 You may omit a network location for a work that was published at 219 least four years before the Document itself, or if the original 220 publisher of the version it refers to gives permission. 221K. For any section Entitled "Acknowledgements" or "Dedications", 222 Preserve the Title of the section, and preserve in the section all 223 the substance and tone of each of the contributor acknowledgements 224 and/or dedications given therein. 225L. Preserve all the Invariant Sections of the Document, 226 unaltered in their text and in their titles. Section numbers 227 or the equivalent are not considered part of the section titles. 228M. Delete any section Entitled "Endorsements". Such a section 229 may not be included in the Modified Version. 230N. Do not retitle any existing section to be Entitled "Endorsements" 231 or to conflict in title with any Invariant Section. 232O. Preserve any Warranty Disclaimers. 233 234If the Modified Version includes new front-matter sections or 235appendices that qualify as Secondary Sections and contain no material 236copied from the Document, you may at your option designate some or all 237of these sections as invariant. To do this, add their titles to the 238list of Invariant Sections in the Modified Version`s license notice. 239These titles must be distinct from any other section titles. 240 241You may add a section Entitled "Endorsements", provided it contains 242nothing but endorsements of your Modified Version by various 243parties--for example, statements of peer review or that the text has 244been approved by an organization as the authoritative definition of a 245standard. 246 247You may add a passage of up to five words as a Front-Cover Text, and a 248passage of up to 25 words as a Back-Cover Text, to the end of the list 249of Cover Texts in the Modified Version. Only one passage of 250Front-Cover Text and one of Back-Cover Text may be added by (or 251through arrangements made by) any one entity. If the Document already 252includes a cover text for the same cover, previously added by you or 253by arrangement made by the same entity you are acting on behalf of, 254you may not add another; but you may replace the old one, on explicit 255permission from the previous publisher that added the old one. 256 257The author(s) and publisher(s) of the Document do not by this License 258give permission to use their names for publicity for or to assert or 259imply endorsement of any Modified Version. 260 261 2625. COMBINING DOCUMENTS 263 264You may combine the Document with other documents released under this 265License, under the terms defined in section 4 above for modified 266versions, provided that you include in the combination all of the 267Invariant Sections of all of the original documents, unmodified, and 268list them all as Invariant Sections of your combined work in its 269license notice, and that you preserve all their Warranty Disclaimers. 270 271The combined work need only contain one copy of this License, and 272multiple identical Invariant Sections may be replaced with a single 273copy. If there are multiple Invariant Sections with the same name but 274different contents, make the title of each such section unique by 275adding at the end of it, in parentheses, the name of the original 276author or publisher of that section if known, or else a unique number. 277Make the same adjustment to the section titles in the list of 278Invariant Sections in the license notice of the combined work. 279 280In the combination, you must combine any sections Entitled "History" 281in the various original documents, forming one section Entitled 282"History"; likewise combine any sections Entitled "Acknowledgements", 283and any sections Entitled "Dedications". You must delete all sections 284Entitled "Endorsements". 285 286 2876. COLLECTIONS OF DOCUMENTS 288 289You may make a collection consisting of the Document and other documents 290released under this License, and replace the individual copies of this 291License in the various documents with a single copy that is included in 292the collection, provided that you follow the rules of this License for 293verbatim copying of each of the documents in all other respects. 294 295You may extract a single document from such a collection, and distribute 296it individually under this License, provided you insert a copy of this 297License into the extracted document, and follow this License in all 298other respects regarding verbatim copying of that document. 299 300 3017. AGGREGATION WITH INDEPENDENT WORKS 302 303A compilation of the Document or its derivatives with other separate 304and independent documents or works, in or on a volume of a storage or 305distribution medium, is called an "aggregate" if the copyright 306resulting from the compilation is not used to limit the legal rights 307of the compilation`s users beyond what the individual works permit. 308When the Document is included in an aggregate, this License does not 309apply to the other works in the aggregate which are not themselves 310derivative works of the Document. 311 312If the Cover Text requirement of section 3 is applicable to these 313copies of the Document, then if the Document is less than one half of 314the entire aggregate, the Document`s Cover Texts may be placed on 315covers that bracket the Document within the aggregate, or the 316electronic equivalent of covers if the Document is in electronic form. 317Otherwise they must appear on printed covers that bracket the whole 318aggregate. 319 320 3218. TRANSLATION 322 323Translation is considered a kind of modification, so you may 324distribute translations of the Document under the terms of section 4. 325Replacing Invariant Sections with translations requires special 326permission from their copyright holders, but you may include 327translations of some or all Invariant Sections in addition to the 328original versions of these Invariant Sections. You may include a 329translation of this License, and all the license notices in the 330Document, and any Warranty Disclaimers, provided that you also include 331the original English version of this License and the original versions 332of those notices and disclaimers. In case of a disagreement between 333the translation and the original version of this License or a notice 334or disclaimer, the original version will prevail. 335 336If a section in the Document is Entitled "Acknowledgements", 337"Dedications", or "History", the requirement (section 4) to Preserve 338its Title (section 1) will typically require changing the actual 339title. 340 341 3429. TERMINATION 343 344You may not copy, modify, sublicense, or distribute the Document except 345as expressly provided for under this License. Any other attempt to 346copy, modify, sublicense or distribute the Document is void, and will 347automatically terminate your rights under this License. However, 348parties who have received copies, or rights, from you under this 349License will not have their licenses terminated so long as such 350parties remain in full compliance. 351 352 35310. FUTURE REVISIONS OF THIS LICENSE 354 355The Free Software Foundation may publish new, revised versions 356of the GNU Free Documentation License from time to time. Such new 357versions will be similar in spirit to the present version, but may 358differ in detail to address new problems or concerns. See 359http://www.gnu.org/copyleft/. 360 361Each version of the License is given a distinguishing version number. 362If the Document specifies that a particular numbered version of this 363License "or any later version" applies to it, you have the option of 364following the terms and conditions either of that specified version or 365of any later version that has been published (not as a draft) by the 366Free Software Foundation. If the Document does not specify a version 367number of this License, you may choose any version ever published (not 368as a draft) by the Free Software Foundation. 369 370 371ADDENDUM: How to use this License for your documents 372 373To use this License in a document you have written, include a copy of 374the License in the document and put the following copyright and 375license notices just after the title page: 376 377 Copyright (c) YEAR YOUR NAME. 378 Permission is granted to copy, distribute and/or modify this document 379 under the terms of the GNU Free Documentation License, Version 1.2 380 or any later version published by the Free Software Foundation; 381 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. 382 A copy of the license is included in the section entitled "GNU 383 Free Documentation License". 384 385If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, 386replace the "with...Texts." line with this: 387 388 with the Invariant Sections being LIST THEIR TITLES, with the 389 Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST. 390 391If you have Invariant Sections without Cover Texts, or some other 392combination of the three, merge those two alternatives to suit the 393situation. 394 395If your document contains nontrivial examples of program code, we 396recommend releasing these examples in parallel under your choice of 397free software license, such as the GNU General Public License, 398to permit their use in free software. 399 400