Provided by: mt-st_1.1-5ubuntu1_amd64 bug

NAME

       mt - control magnetic tape drive operation

SYNOPSIS

       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  commands  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 on which to  operate  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 postfix k , M , or G can be used to give  counts  in
       units of 1024, 1024 * 1024, or 1024 * 1024 * 1024, respectively.

       The  available  operations  are listed below.  Unique abbreviations 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 filemarks.

       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 end of tape.

       rewind Rewind the tape.

       offline, rewoffl, eject
              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 position (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 initiator-specified partition size  and  partition
              support must be enabled for the drive.

       load   (SCSI  tapes)  Send the load command to the tape drive. The drives usually load the
              tape when a new cartridge is inserted. The argument count can usually  be  omitted.
              Some  HP changers load tape n if the count 10000 + n is given (a special funtion in
              the Linux st driver).

       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 density codes to standard output.

       drvbuffer
              (SCSI  tapes)  Set  the  tape  drive  buffer  code to number.  The proper value for
              unbuffered operation is zero and "normal" buffered operation one. The  meanings  of
              other  values  can  be found in the drive documentation or, in the 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  necessary,  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)

              no-wait        don't wait until rewind, etc. complete

              auto-lock      automatically lock/unlock drive door

              def-writes     the block size and density are for writes

              can-bsr        drive can space backwards as 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

              sili           Set the SILI bit is when reading in variable block  mode.  This  may
                             speed  up  reading blocks shorter than the read byte count. Set this
                             option only if you know that the drive supports  SILI  and  the  HBA
                             reliably  returns  transfer  residual  byte  counts. Requires kernel
                             version >= 2.6.26.

              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  the  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.

       stshowoptions
              (SCSI  tapes)  Print  the currently enabled options for the device. Requires kernel
              version >= 2.6.26 and sysfs must be mounted at /sys.

       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 compression 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 superuser.

       stlongtimeout
              sets  the  long timeout for the device. The value is given in seconds. Allowed only
              for the superuser.

       stsetcln
              set the cleaning request interpretation parameters.

       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.Makisara@kolumbus.fi>.

COPYRIGHT

       The  program  and the manual page are copyrighted by Kai Makisara, 1998-2008.  They can be
       distributed according to the GNU Copyleft.

SEE ALSO

       st(4)

                                            April 2008                                      MT(1)