NAME
mt — magnetic tape manipulating program
SYNOPSIS
mt
[-f
tapename]
command
[count]
Obsolescent
mt
[-t
tapename]
command
[count]
DESCRIPTION
mt
is used to give commands to the tape drive.
If
tapename
is not specified, the environment variable
TAPE
is used; if
TAPE
is not defined, the default drive is used.
mt
winds the tape in the requested direction
(forward or backward), stopping after the specified
count
EOF
marks or records are passed.
If
count
is not specified, one is assumed.
Each
EOF
mark counts as one record.
When winding backwards, the tape always stops at the
BOT
marker, regardless of the number remaining in
count.
mt
accepts the following
commands:
- eof
Write
count
EOF
marks.
- fsf
Forward space
count
files.
- fsr
Forward space
count
records.
- bsf
Backward space
count
files.
- bsr
Backward space
count
records.
- rew
Rewind tape.
- offl
Rewind tape and go offline.
- eod
Seek to end of data (DDS and QIC drives only).
- smk
Write
count
setmarks (DDS drives only).
- fss
Forward space
count
setmarks (DDS drives only).
- bss
Backward space
count
setmarks (DDS drives only).
- status
Print status information about the tape drive.
- res
Reserve tape drive for sole use by the host issuing the
mt
command (stape or estape driver only).
- rel
Release tape drive from sole use by the host issuing the
mt
command (stape or estape driver only).
Spacing operations (back or forward space file or record)
leave the tape positioned past the object being spaced to
in the direction of motion.
That is, backspacing a file
leaves the the tape positioned before the file mark,
forward spacing a file leaves the tape positioned after the file mark.
This is consistent with all classical usage on tapes.
WARNINGS
Only raw, no-rewind Berkeley-type devices should be specified.
This type of device will not reposition the tape upon close.
An example of such a device is
/dev/rmt/0mnb
or
/dev/rtape/tape1_BESTnb.
See
mt(7)
for more details.
It is possible to wind the tape beyond the
EOT
marker and off the end of the reel.
A reservation may only be cleared with a release by the host
that issued the original reserve. In the event that the host
that holds the reservation is no longer available, the
st
command may be used to reclaim the device by issuing a bus
device reset. See
st(1M)
for more details.
The reserve/release functionality can only be issued to drives
using the
stape
or
estape
driver.
EXAMPLES
Rewind the tape associated with the device file
/dev/rmt/0mnb
or
/dev/rtape/tape1_BESTnb
(if legacy DSF is disabled):
FILES
- /dev/rmt/*
Raw magnetic tape interface (stape)
- /dev/rtape/*
Raw magnetic tape interface (estape)
- /dev/rmt/0mnb
Default tape interface.
If legacy DSF is disabled, the default value is
/dev/rtape/tape1_BESTnb.
AUTHOR
mt
was developed by the University of California, Berkeley.