I have a tar file which gets updated many times, and there are multiple copies of the same file. I've found the latest version of the file gets extracted using -x.
For example: I have a save.tar file that contains 3 versions of a.txt: a.txt version1 "this is not done" a.txt version2 "this is correct." a.txt version3 "this is broke."
How do I extract a.txt (the version2)
Approx. 40 years ago, there was a discussion whether tar could get an option to specify the n-th occurence that should be extracted but I am not sure whether this is a good idea.
With a standard tar implementation, you could call:
tar xvwf archive.tar
and then interactively confirm the extraction for the "right" version.
With star, there is an additional method:
star -xv < archive.tar -find -mtime +some-time-spec -mtime -other-time-spec
and use two useful time specifiers to select the "right" version.
See: http://schilytools.sourceforge.net/man/man1/star.1.html
You of course need to use an additional path name selector in case that the archive file contains more differen filenames. So with a standard tar, this becomes:
tar xvwf archive.tar a.txt
and with star it becomes:
star -xv < archive.tar a.txt -find -mtime +some-time-spec -mtime -other-time-spec
or:
star -xv < archive.tar -find -path a.txt -mtime +some-time-spec -mtime -other-time-spec
