This is a FAQ. Typing perldoc -q difference or looking at perlfaq4, How do I compute the intersection of two arrays shows you how to do it for simple arrays. You haven't specified, but I guess want to use the third column in your files as key instead of using the whole line, so you will have to do some extra work there.

In reply to Re: Comparing arrays ... by Corion
in thread Comparing arrays ... by fwed

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