(tar)mt

Tape Positioning

Many

The `mt' Utility
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     *(This message will disappear, once this node revised.)*

FIXME: is it true that this only works on non-block devices?  should
FIXME: explain the difference, xref to block-size (fixed or variable).

   You can use the `mt' utility to advance or rewind a tape past a
specified number of archive files on the tape.  This will allow you to
move to the beginning of an archive before extracting or reading it, or
to the end of all the archives before writing a new one.
FIXME: why isn't there an "advance 'til you find two tape marks together"?

   The syntax of the `mt' command is:

     mt [-f TAPENAME] OPERATION [NUMBER]

   where TAPENAME is the name of the tape device, NUMBER is the number
of times an operation is performed (with a default of one), and
OPERATION is one of the following:

FIXME: is there any use for record operations?

`eof'
`weof'
     Writes NUMBER tape marks at the current position on the tape.

`fsf'
     Moves tape position forward NUMBER files.

`bsf'
     Moves tape position back NUMBER files.

`rewind'
     Rewinds the tape. (Ignores NUMBER).

`offline'
`rewoff1'
     Rewinds the tape and takes the tape device off-line. (Ignores
     NUMBER).

`status'
     Prints status information about the tape unit.
FIXME: is there a better way to frob the spacing on the list?

   If you don't specify a TAPENAME, `mt' uses the environment variable
TAPE; if TAPE does not exist, `mt' uses the device `/dev/rmt12'.

   `mt' returns a 0 exit status when the operation(s) were successful,
1 if the command was unrecognized, and 2 if an operation failed.

FIXME: new node on how to find an archive?
   If you use `--extract' (`-x') with the `--label=ARCHIVE-LABEL' (`-V
ARCHIVE-LABEL') option specified, `tar' will read an archive label (the
tape head has to be positioned on it) and print an error if the archive
label doesn't match the ARCHIVE-NAME specified.  ARCHIVE-NAME can be
any regular expression.  If the labels match, `tar' extracts the
archive.
FIXME: xref Archive Label
   .
FIXME: xref Matching Format Parameters
   .
FIXME: fix cross references

   `tar --list --label' will cause `tar' to print the label.

FIXME: program to list all the labels on a tape?