make output line buffered if selecting only some of the entries

[unix-history] / usr / src / usr.bin / mt / mt.1

.\" Copyright (c) 1981 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms are permitted
.\" provided that the above copyright notice and this paragraph are
.\" duplicated in all such forms and that any documentation,
.\" advertising materials, and other materials related to such
.\" distribution and use acknowledge that the software was developed
.\" by the University of California, Berkeley.  The name of the
.\" University may not be used to endorse or promote products derived
.\" from this software without specific prior written permission.
.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
.\" IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
.\"
.\"	@(#)mt.1	6.3 (Berkeley) %G%
.\"
.UC 7
.TH MT 1 ""
.UC 4
.SH NAME
mt \- magnetic tape manipulating program
.SH SYNOPSIS
.B mt
[
.B \-f
.I tapename
]
.I command
[
.I count
]
.SH DESCRIPTION
.I Mt
is used to give commands to a magnetic tape drive.
If a tape name is not specified, the environment variable
TAPE is used;  if TAPE does not exist,
.I mt
uses the device
.IR /dev/rmt12 .
Note
that
.I tapename
must reference a raw (not block) tape device.
By default
.I mt
performs the requested operation once.  Operations
may be performed multiple times by specifying
.IR count .
.PP
The available commands are listed below.  Only as many
characters as are required to uniquely identify a command
need be specified.
.TP
.BR eof , " weof"
Write 
.I count
end-of-file marks at the current position on the tape.
.TP
.B fsf
Forward space
.I count
files.
.TP
.B fsr
Forward space 
.I count
records.
.TP
.B bsf
Back space 
.I count
files.
.TP 
.B bsr
Back space
.I count
records.
.TP
.B rewind
Rewind the tape
.RI ( Count
is ignored). 
.TP
.BR offline , " rewoffl"
Rewind the tape and place the tape unit off-line
.RI ( Count
is ignored).
.TP
.B status
Print status information about the tape unit.
.PP
.I 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 FILES
.DT
/dev/rmt*	Raw magnetic tape interface
.SH "SEE ALSO"
mtio(4), dd(1), ioctl(2), environ(7)