usr/src/usr.bin/mt/mt.1

.\" Copyright (c) 1981, 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)mt.1        6.5 (Berkeley) %G%
.\"
.Dd
.Os BSD 4.4
.Dt MT 1
.Os BSD 4
.Sh NAME
.Nm mt
.Nd magnetic tape manipulating program
.Sh SYNOPSIS
.Nm mt
.Op Fl f Ar tapename
.Ar command
.Op Ar count
.Sh DESCRIPTION
.Nm Mt
is used to give commands to a magnetic tape drive.
If a tape name is not specified, the environment variable
.Ev TAPE
is used;  if
.Ev TAPE
does not exist,
.Nm mt
uses the device
.Pa /dev/rmt12 .
Note
that
.Ar tapename
must reference a raw (not block) tape device.
By default
.Nm mt
performs the requested operation once.  Operations
may be performed multiple times by specifying
.Ar count  .
.Pp
The available commands are listed below.  Only as many
characters as are required to uniquely identify a command
need be specified.
.Tp Cm eof , weof
Write
.Ar count
end-of-file marks at the current position on the tape.
.Tp Cm fsf
Forward space
.Ar count
files.
.Tp Cm fsr
Forward space
.Ar count
records.
.Tp Cm bsf
Back space
.Ar count
files.
.Tp Cm bsr
Back space
.Ar count
records.
.Tp Cm rewind
Rewind the tape
(Count is ignored).
.Tp Cm offline , rewoffl
Rewind the tape and place the tape unit off-line
(Count is ignored).
.Tp Cm status
Print status information about the tape unit.
.Tp
.Pp
.Nm Mt
returns a 0 exit status when the operation(s) were successful,
1 if the command was unrecognized, and 2 if an operation failed.
.Sh ENVIRONMENT
If the following environment variable exists, it is utilized by
.Nm mt .
.Tw Fl
.Tp Ev TAPE
.Nm Mt
checks the
.Ev TAPE
environment variable if the
argument
.Ar tapename
is not given.
.Sh FILES
.Dw /dev/rmt*
.Di L
.Dp Pa /dev/rmt*
Raw magnetic tape interface
.Dp
.Sh SEE ALSO
.\".Xr mtio 4 ,
.Xr dd 1 ,
.Xr ioctl 2 ,
.Xr environ 7
.Sh HISTORY
.Nm Mt
appeared in 4.3 BSD.
.\" mt.1: mtio(4) missing