mt
MT(1) MT(1)NAME
mt - control magnetic tape drive operationSYNOPSIS
mt [-h] [-f device] operation [count] [arguments...]DESCRIPTION
This manual page documents the tape control program mt. mt performs the given operation, which must be one of the tape operations listed below, on a tape drive. The com mands can also be listed by running the program with the -h option. The version of mt is printed with the -v or --version option. The path of the tape device to operate on can be given with the -f or -t option. If neither of those options is given, and the environment variable TAPE is set, it is used. Otherwise, a default device defined in the file /usr/include/sys/mtio.h is used. Some operations optionally take an argument or repeat count, which can be given after the operation name and defaults to 1. The available operations are listed below. Unique abbre viations are accepted. Not all operations are available on all systems, or work on all types of tape drives. fsf Forward space count files. The tape is positioned on the first block of the next file. fsfm Forward space count files. The tape is positioned on the last block of the previous file. bsf Backward space count files. The tape is positioned on the last block of the previous file. bsfm Backward space count files. The tape is positioned on the first block of the next file. asf The tape is positioned at the beginning of the count file. Positioning is done by first rewinding the tape and then spacing forward over count file marks. fsr Forward space count records. bsr Backward space count records. fss (SCSI tapes) Forward space count setmarks. bss (SCSI tapes) Backward space count setmarks. eod, seod Space to end of valid data. Used on streamer tape drives to append data to the logical and of tape. rewind Rewind the tape. offline, rewoffl Rewind the tape and, if applicable, unload the tape. retension Rewind the tape, then wind it to the end of the reel, then rewind it again. weof, eof Write count EOF marks at current position. wset (SCSI tapes) Write count setmarks at current posi tion (only SCSI tape). erase Erase the tape. status Print status information about the tape unit. (If the density code is "no translation" in the status output, this does not affect working of the tape drive.) seek (SCSI tapes) Seek to the count block on the tape. This operation is available on some Tandberg and Wangtek streamers and some SCSI-2 tape drives. The block address should be obtained from a tell call earlier. tell (SCSI tapes) Tell the current block on tape. This operation is available on some Tandberg and Wangtek streamers and some SCSI-2 tape drives. setpartition (SCSI tapes) Switch to the partition determined by count. The default data partition of the tape is numbered zero. Switching partition is available only if enabled for the device, the device supports multiple partitions, and the tape is formatted with multiple partitions. partseek (SCSI tapes) The tape position is set to block count in the partition given by the argument after count. The default partition is zero. mkpartition (SCSI tapes) Format the tape with one (count is zero) or two partitions (count gives the size of the second partition in megabytes). The tape drive must be able to format partitioned tapes with ini tiator-specified partition size and partition sup port must be enabled for the drive. load (SCSI tapes) Load the tape into the drive. lock (SCSI tapes) Lock the tape drive door. unlock (SCSI tapes) Unlock the tape drive door. setblk (SCSI tapes) Set the block size of the drive to count bytes per record. setdensity (SCSI tapes) Set the tape density code to count. The proper codes to use with each drive should be looked up from the drive documentation. densities (SCSI tapes) Write explanation of some common den sity codes to standard output. drvbuffer (SCSI tapes) Set the tape drive buffer code to num ber. The proper value for unbuffered operation is zero and "normal" buffered operation one. The mean ings of other values can be found in the drive doc umentation or, in case of a SCSI-2 drive, from the SCSI-2 standard. compression (SCSI tapes) The compression within the drive can be switched on or off using the MTCOMPRESSION ioctl. Note that this method is not supported by all drives implementing compression. For instance, the Exabyte 8 mm drives use density codes to select compression. stoptions (SCSI tapes) Set the driver options bits for the device to the defined values. Allowed only for the superuser. The bits can be set either by oring the option bits from the file /usr/include/linux/mtio.h to count, or by using the following keywords (as many keywords can be used on the same line as nec essary, unambiguous abbreviations allowed): buffer-writes buffered writes enabled async-writes asynchronous writes enabled read-ahead read-ahead for fixed block size debug debugging (if compiled into driver) two-fms write two filemarks when file closed fast-eod space directly to eod (and lose file number) auto-lock automatically lock/unlock drive door def-writes the block size and density are for writes can-bsr drive can space backwards well no-blklimits drive doesn't support read block limits can-partitions drive can handle partitioned tapes scsi2logical seek and tell use SCSI-2 logical block addresses instead of device dependent addresses sysv enable the System V semantics stsetoptions (SCSI tapes) Set selected driver options bits. The methods to specify the bits to set are given above in description of stoptions. Allowed only for the superuser. stclearoptions (SCSI tapes) Clear selected driver option bits. The methods to specify the bits to clear are given above in description of stoptions. Allowed only for the superuser. stwrthreshold (SCSI tapes) The write threshold for the tape device is set to count kilobytes. The value must be smaller than or equal to the driver buffer size. Allowed only for the superuser. defblksize (SCSI tapes) Set the default block size of the device to count bytes. The value -1 disables the default block size. The block size set by setblk overrides the default until a new tape is inserted. Allowed only for the superuser. defdensity (SCSI tapes) Set the default density code. The value -1 disables the default density. The density set by setdensity overrides the default until a new tape is inserted. Allowed only for the superuser. defdrvbuffer (SCSI tapes) Set the default drive buffer code. The value -1 disables the default drive buffer code. The drive buffer code set by drvbuffer overrides the default until a new tape is inserted. Allowed only for the superuser. defcompression (SCSI tapes) Set the default compression state. The value -1 disables the default compression. The com pression state set by compression overrides the default until a new tape is inserted. Allowed only for the superuser. sttimeout sets the normal timeout for the device. The value is given in seconds. Allowed only for the supe ruser. stlongtimeout sets the long timeout for the device. The value is given in seconds. Allowed only for the superuser. mt exits with a status of 0 if the operation succeeded, 1 if the operation or device name given was invalid, or 2 if the operation failed.AUTHOR
The program is written by Kai Makisara <Kai.Mak isara@metla.fi>. COPYRIGHT The program and the manual page are copyrighted by Kai Makisara, 1998-2000. They can be distributed according to the GNU Copyleft.SEE ALSO
st(4) November 2000 MT(1)