Today I made a typo in the shell: instead of m trc
(m
being my alias for less
and trc
the name of some trace file), I accidentally typed mt rc
. To my surprise, the system didn’t respond with zsh: command not found: mt
. It responded with this message:
mt: invalid argument ‘rc’ for ‘operation’
Valid arguments are:
- ‘eof’, ‘weof’
- ‘fsf’
- ‘bsf’
- ‘fsr’
- ‘bsr’
- ‘rewind’
- ‘offline’, ‘rewoffl’, ‘eject’
- ‘status’
- ‘bsfm’
- ‘eom’
- ‘retension’
- ‘erase’
- ‘asf’
- ‘fsfm’
- ‘seek’
Say, what? I’ve been using Unix-like systems for REDACTED years, but I don’t remember ever having used an mt
command. And so I checked the fine manual:
MT(1) GNU CPIO MT(1)
NAME
mt - control magnetic tape drive operation
SYNOPSIS
mt [-V] [-f device] [--file=device] [--rsh-command=command] [--version]
operation [count]
DESCRIPTION
This manual page documents the GNU version of mt. mt performs the
given operation, which must be one of the tape operations listed below,
on a tape drive.
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 com‐
mand line option (see below), which also overrides the environment
variable.
...
Now I admit that I am not too keen to upgrade my Ubuntu, but it’s not that ancient, either. It turns out that an Ubuntu distribution released in 2018 actually installs a program to control magnetic tape drive operation! I know, I know, the program is likely useful for other things as well, and tar
is technically also short for “tape archiver”, but it still feels a bit silly to carry this cruft into the 21st century.
And people say that Windows is arcane in its support for DOS graphics and x86 addressing modes.