Specify root dir inside tarball

Question

Is there a way to execute

tar cjvf foo.tar.bz2 project-root

Such that when the tarball is extracted, it doesn't extract to project-root, but instead extracts to something else? i.e.

tar xjvf foo.tar.bz2
cd something-else
# see all files that were within original project-root

I'm aware of -C, but I want it such that something-else doesn't exist yet.

Answer 1

You can rename project-root inside the tarball with the 7-zip GUI (and probably other archiver programs as well), but this may do a full decompression-recompression cycle on compressed tarballs. (Read: this may take a while on large, heavily-compressed tarballs.)

The best way to do what you want is to change the name before creating the tarball. A simple way would be to temporarily rename project-root to something-else:

# temporary rename; tar; restore original name
$ mv project-root something-else ; tar cjf foo.tar.bz2 something-else ; mv something-else project-root

I'd probably go a little more complicated: make a copy with the name I want in the tarball. This avoids potential bugs or missed steps in whatever fix-it-up-later process might be employed, and I might want to keep both copies around for other purposes.

# make me a copy
$ ( cd project-root ; tar cf - . ) | ( mkdir something-else; cd something-else; tar xf - )

# test the copy here if needed
$ diff -r --brief project-root/ something-else/

# create my tarball
$ tar cjf foo.tar.bz2 something-else