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 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 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. Posi-
    tioning 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 and 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 opera-
    tion 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 par-
    tition 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 sup-
    port 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 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)

    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 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  stop-
    tions. 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 supe-
    ruser.

    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 sec-
    onds. 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 opera-
    tion or device name given was invalid, or 2 if the operation failed.

AUTHOR
    The program is written by Kai Makisara <Kai.Makisara@metla.fi>.

COPYRIGHT
    The program and the manual page are copyrighted by Kai Makisara,
    1998-2001. They can be distributed according to the GNU Copyleft.

SEE ALSO
    st(4)