Control filename stored in tar archive

Question

I want to make a tar archive containing various files scattered around the filesystem:

$ tar czvf outfile.tar.gz /some/file /some/other/filename

This creates the archive successfully, but when I extract it, the files are still in a directory tree matching the original locations:

$ tar xvf outfile.tar.gz
some/file
some/other/filename

I'd like to have them both extracted to the current directory, such that file and filename are created on their own.

I can do this at extract time using --transform, e.g.:

$ tar xvf outfile.tar.gz --transform=s,.*/,,

This does what I want, but it's a bit annoying to have to use an obscure option at extract-time, makes it more difficult to send to others, and so forth.

I could do it at create-time like this:

$ cd tmpdir
$ cp /some/file /some/other/filename .
$ tar czvf outfile.tar.gz *

But that seems a bit heavyweight, especially if there are large files or a lot of them.

Is there any way to control the filenames that tar stores at create-time directly?

Answer 1

Doesn't --transform work when creating the archive, then? It seems to work on my GNU tar 1.27.1:

$ tar czf out.tar.gz some/foo some/other/bar --transform=s,.*/,,
$ tar tzf out.tar.gz 
foo
bar

If it doesn't work, another possibility would be to make links to the files in the current directory (as you did with cp, but with ln):

$ ln /some/foo /some/other/bar .
$ tar czf out.tar.gz foo bar

Answer 2

There is a very useful tool named tardy that can be used to edit tar files:

tardy -Remove_Prefix 55 outfile.tar.gz transformed.tar.gz

Here 55 is an arbitrary number larger than the maximum depth of all directories in outfile.tar.gz. -Remove_Prefix 55 tells tardy to remove (at most) 55 leading directories from filenames.