Absolute File Names
_(This message will disappear, once this node revised.)_
Do not strip leading slashes from file names, and permit file names
containing a `..' file name component.
By default, GNU `tar' drops a leading `/' on input or output, and
complains about file names containing a `..' component. This option
turns off this behavior.
When `tar' extracts archive members from an archive, it strips any
leading slashes (`/') from the member name. This causes absolute
member names in the archive to be treated as relative file names. This
allows you to have such members extracted wherever you want, instead of
being restricted to extracting the member in the exact directory named
in the archive. For example, if the archive member has the name
`/etc/passwd', `tar' will extract it as if the name were really
File names containing `..' can cause problems when extracting, so
`tar' normally warns you about such files when creating an archive, and
rejects attempts to extracts such files.
Other `tar' programs do not do this. As a result, if you create an
archive whose member names start with a slash, they will be difficult
for other people with a non-GNU `tar' program to use. Therefore, GNU
`tar' also strips leading slashes from member names when putting
members into the archive. For example, if you ask `tar' to add the
file `/bin/ls' to an archive, it will do so, but the member name will
If you use the `--absolute-names' (`-P') option, `tar' will do none
of these transformations.
To archive or extract files relative to the root directory, specify
the `--absolute-names' (`-P') option.
Normally, `tar' acts on files relative to the working
directory--ignoring superior directory names when archiving, and
ignoring leading slashes when extracting.
When you specify `--absolute-names' (`-P'), `tar' stores file names
including all superior directory names, and preserves leading slashes.
If you only invoked `tar' from the root directory you would never need
the `--absolute-names' (`-P') option, but using this option may be more
convenient than switching to root.
Preserves full file names (including superior directory names) when
archiving files. Preserves leading slash when extracting files.
`tar' prints out a message about removing the `/' from file names.
This message appears once per GNU `tar' invocation. It represents
something which ought to be told; ignoring what it means can cause very
serious surprises, later.
Some people, nevertheless, do not want to see this message. Wanting
to play really dangerously, one may of course redirect `tar' standard
error to the sink. For example, under `sh':
$ tar -c -f archive.tar /home 2> /dev/null
Another solution, both nicer and simpler, would be to change to the `/'
directory first, and then avoid absolute notation. For example:
$ (cd / && tar -c -f archive.tar home)
$ tar -c -f archive.tar -C / home
automatically generated byinfo2html