Linux mt command
On Unix-like operating systems, the mt command controls a magnetic tape device.
This page covers the GNU/Linux version of mt.
Description
The default tape device to operate on is taken from the file /usr/include/sys/mtio.h when mt is compiled. It can be overridden by giving a device file name in the environment variable TAPE or by a command line option (see below), that also overrides the environment variable.
The device must be a character special file or a remote tape drive. To use a tape drive on another machine as the archive, use a file name that starts with 'HOSTNAME:'. The hostname can be preceded by a username and an '@' to access the remote tape drive as that user, if you have permission to do so (typically an entry in that user's '~/.rhosts' file).
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. Some operations optionally take a repeat count, which can be given after the operation name and defaults to 1.
Syntax
mt [-V] [-f device] [--file=device] [--rsh-command=command] [--version] operation [count]
Operations
| eof, weof | Write count EOF marks at current position. |
| fsf | Forward space count files. The tape is positioned on the first block of the next file. |
| bsf | Backward space count files. The tape is positioned on the first block of the next file. |
| fsr | Forward space count records. |
| bsr | Backward space count records. |
| bsfm | Backward space count file marks. The tape is positioned on the beginning-of-the-tape side of the file mark. |
| fsfm | Forward space count file marks. The tape is positioned on the beginning-of-the-tape side of the file mark. |
| asf | Absolute space to file number count. Equivalent to rewind followed by fsf count. |
| seek | Seek to block number count. |
| eom | Space to the end of the recorded media on the tape (for appending files onto tapes). |
| rewind | Rewind the tape. |
| offline, rewoffl | Rewind the tape and, if applicable, unload the tape. |
| status | Print status information about the tape unit. |
| retension | Rewind the tape, then wind it to the end of the reel, then rewind it again. |
| erase | Erase the tape. |
Options
| -f, --file=device | Use device as the file name of the tape drive to operate on. To use a tape drive on another machine, use a file name that starts with 'HOSTNAME:'. The hostname can be preceded by a username and an '@' to access the remote tape drive as that user, if you have permission to do so (typically an entry in that user's '~/.rhosts' file). |
| --rsh-command=command | Notifies mt that it should use command to communicate with remote devices instead of /usr/bin/ssh or /usr/bin/rsh. |
| -V, --version | Print the version number of mt. |
Exit status
mt exits with a status of 0 if the operation succeeded, 1 if the operation or device name given was invalid, or 2 if the operation failed.
Related commands
tar — Create, modify, list the contents of, and extract files from tar archives.
tcopy — Copy a magnetic tape.