The simple answer for your problem would appear to be diff, a standard *nix command and available as a GUI in Windows as WinDiff. Is there a reason you cannot use these rather than reinventing the wheel? If you need to do it in Perl, this is a FAQ: How do I compute the difference of two arrays? How do I compute the intersection of two arrays?

In reply to Re: Pulling out data from one file thats not in another by kennethk
in thread Pulling out data from one file thats not in another by Angharad

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