MT(1) OpenBSD Reference Manual MT(1)NAME
mt, eject - magnetic tape and removable media manipulating program
SYNOPSIS
mt [-f device] command [count]
eject [-t] device
DESCRIPTION
The mt utility sends commands to a magnetic tape drive. By default, mt
performs the requested operation once. Operations may be performed
multiple times by specifying count. Note that device must reference a
raw (not block) tape device. If device is of the form ``host:device'' or
``user@host:device'', mt writes to the named tape device on the remote
host using rmt(8). eject is simply an alias for mt, with the offline
command specified. eject may also be used to eject other types of
removable media.
The options for mt are as follows:
-f device
Operate on the device specified.
The options for eject are as follows:
-t Insert the device instead of ejecting. For the cd(4) driver,
this requests that the tray be closed.
The available commands are listed below. Only as many characters as are
required to uniquely identify a command need be specified.
eof, weof Write count end-of-file marks at the current position on the
tape.
fsf Forward space count files.
fsr Forward space count records.
bsf Back space count files.
bsr Back space count records.
rewind Rewind the tape (count is ignored).
offline, rewoffl
Rewind the tape and place the tape unit off-line (count is
ignored). On non-tape removable media, the offline command
causes the media to be ejected when the last operation on it
closes (i.e., the filesystem is unmounted).
status Print status information about the tape unit.
retension Retension the tape (if this operation is supported by the tape
unit).
erase Erase the tape (if this operation is supported by the tape
unit).
eom Forward space to the end of the media.
blocksize Set the tape blocksize to count bytes.
density Set the tape density code to count as specified in the SCSI2
specification.
If a tape name is not specified, and the environment variable TAPE does
not exist, mt uses the device /dev/rst0. The TAPE variable is ignored by
eject.
ENVIRONMENT
If the following environment variable exists, it is utilized by mt.
TAPE mt checks the TAPE environment variable if the argument
device is not given.
FILES
/dev/rst* raw SCSI tape interface
/dev/rmt* raw magnetic tape interface
/usr/src/sys/scsi/scsi_tape.h list of SCSI2 density codes
EXIT STATUS
mt returns a 0 exit status when the operation(s) were successful, 1 if
the command was unrecognized, and 2 if an operation failed.
EXAMPLES
Eject the first CD device. This will work even if there is no CD in the
drive:
$ eject /dev/rcd0c
SEE ALSOcdio(1), chio(1), dd(1), ioctl(2), mtio(4)HISTORY
The mt utility appeared in Version 2 AT&T UNIX.
OpenBSD 4.9 September 3, 2010 OpenBSD 4.9
