tar – extract discarding directory structure

Question

unzip has a nifty option -j, whereby the directory structure of the archive is discarded, and all files are extracted into the same directory.

Is there a way of making tar work in the same way? Nothing in the man page seems to indicate so.

So, is there an alternative, preferably Free Software, tool that will do that?

Answer 1

GNU tar lives on featuritis, so naturally also has some options for that.
http://www.gnu.org/software/tar/manual/html_node/transform.html

If you just want to remove a few path segments, then --strip-components=n or --strip=n will often do:

 tar xvzf tgz --strip=1

But it's also possible to regex-rewrite the files to be extracted (flags are --transform or --xform and accept ereg with the /x modifer):

 tar xvzf tgz --xform='s#^[^/]+#.#x'
                 # or 's#^.+/##x' for discarding all paths

For listing a tar you need the additional --show-transformed option:

 tar tvzf tgz --show-transformed --strip=1 --xform='s/abc/xyz/x'

I believe the rewriting options also work for packing, not just for extracting. But pax has obviously a nicer syntax.

Answer 2

You can do it fairly easily in two steps. Adapt as necessary:

$ mkdir /tmp/dirtree
$ tar xfz /path/to/archive -C /tmp/dirtree
$ find /tmp/dirtree -type f -exec mv -i {} . \;
$ rm -rf /tmp/dirtree

Answer 3

pax can do it:

pax -v -r -s '/.*\///p' < archive.tar

or

zcat archive.tar.gz | pax -v -r -s '/.*\///p'

You can check the name replacement operation first by omitting the -r option.

Answer 4

A possible solution that doesn't require installing anything.

1. use a tar tvf to grab all the files from the tarball

2. Extract those files individually - have tar extract to stdout & redirect to $filename

   tar -tvf $1 | grep -v "^d" | \
                 awk '{for(i=6;i<NF+1;i++) {printf "%s ",$i};print ""}' |\
                 while read filename
                 do
                    tar -O -xf $1 "$filename" > `basename "$filename"`
                 done
   

save as extract.sh and run as extract.sh myfile.tar. It will also overwrite any duplicate filenames encountered in the directories pulled from the tarball.

Answer 5

tar xf foo.tar.gz foo/path/to/file/bar.mp3 -O > bar.mp3

The -O option extracts a file to standard out, and > redirects that output into a file. So in my example I'm extracting foo.mp3 and redirecting it into bar.mp3. The file names are arbitrary.