You can restore one or more specific file from an tar archive by specifying the files as argument to the 'tar xf' command.
Code:
$ tar cvf save.tar Test
Test/
Test/123
Test/a11
Test/bob.txt
Test/john.txt
Test/lulu.txt
Test/toto.txt
$ tar tvf save.tar
drwxr-xr-x Jean-Pierre/Aucun 0 2007-05-20 10:32 Test/
-rw-r--r-- Jean-Pierre/Aucun 0 2007-05-20 10:32 Test/123
-rw-r--r-- Jean-Pierre/Aucun 0 2007-05-20 10:32 Test/a11
-rw-r--r-- Jean-Pierre/Aucun 4 2007-05-19 17:14 Test/bob.txt
-rw-r--r-- Jean-Pierre/Aucun 5 2007-05-19 17:14 Test/john.txt
-rw-r--r-- Jean-Pierre/Aucun 5 2007-05-19 17:13 Test/lulu.txt
-rw-r--r-- Jean-Pierre/Aucun 5 2007-05-19 17:13 Test/toto.txt
$ tar xvf save.tar Test/123
Test/123
$ tar xvf save.tar Test/123 Test/bob.txt
Test/123
Test/bob.txt
$
