I had a very similar question the other day. You can find my complete code on the last post of this thread.

http://www.perlmonks.org/?node_id=968493

The cpan utility I used is here. (though there is a way to use grep)

http://search.cpan.org/dist/Array-Utils/Utils.pm

Basically you need to open each file and read them into separate arrays. Then cycle through and find the matches.

In reply to Re^3: Extract common lines from 2 files by Hellhound4
in thread Extract common lines from 2 files by great_riyaz

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