Documentation/scsi/st.rst

22 directly with ioctls. This is administratively a very simple and
24 in a multiuser environment the next user finds the tape parameters in
29 These parameters can be programmed to come into effect either when a
35 the tape is rewritten from the beginning (or a new tape is written
37 does not perform auto-detection well enough and there is a single
38 "sensible" mode for the device. An example is a DAT drive that is
50 system manager (root). When specification of a new mode is started,
51 the configuration of mode 0 is used to provide a starting point for
58 parameters are reset when a new tape is loaded).
65 tables (and will not do that in future). Instead of that, a utility
68 alternative is to make a small script that uses mt to set the defaults
82 be a multiple of the block size. This is not required when reading but
91 writing and the last operation has been a write. Two filemarks can be
96 as a synchronization point, i.e., all remaining data form the drive buffers is
102 operation is MTWEOFI, close() does not write a filemark. This can be used if
107 write, a filemark is written before moving tape.
115 device can be opened for writing even if there is a write protected
144 is the tape number and y a character corresponding to the mode (none, l, m,
145 a). For example, the directories for the first tape device are (assuming four
156 enabled driver and mode options. The value in the file is a bit mask where the
176    directory (where <match> is a directory entry from /sys/class/scsi_tape
211       - The number of times during a read or write we found
212 	the residual amount to be non-zero. This should mean that a program
213 	is issuing a read larger thean the block size on tape. For write
240 defining the value of the symbol ST_SYSV. The semantics differ when a
252 is not possible, a driver buffer allocated at run-time is used. If
274 cause a surprise when moving from 2.4. There small writes (e.g., tar without
276 2.6. Direct i/o can be turned off to solve this problem but a better solution
291 a filemark to truncate a read request or that don't like backspacing.
301    (PAGE_SIZE << ST_FIRST_ORDER) bytes if the system can give a chunk of
325 returns -1 and errno is set to ENOSPC. To enable writing a trailer,
335 are configurable when the driver is loaded as a module. The keywords are:
364 pairs are separated with a comma (no spaces allowed). A colon can be
388 (look for a package mt-st* from the Linux ftp sites; the GNU mt does
436 	block numbers in the status are not valid after a seek.
530 	        writing a filemark, don't wait for it to complete). Please
560 	   contains the new default. If the bits 8-15 are set to a
572 	   known to take a long time. The default is 14000 seconds
578 	   generic status bit GMT_CLN if a cleaning request bit pattern
585 	   a mask to select the relevant bits (the bits 9-16), and the
647 (The driver always backs over a filemark crossed by read ahead if the
659 and disabled by writing a '0' (disable) or '1' (enable) to the sysfs