One way to do it would be to read each file, pulling out the mac addresses, and then use the mac addresses as hash keys. Something like "$found{$addr}++". Once you've done that, having read each file, %found will contain a list of all mac addresses, and a count for each address. If count == 30, you know that particular address was found in all 30 files, and you can output that key to your new file.

Hope that helps...

If none of this makes sense, start with a less ambitious project, such as reading "Learning Perl" (the Llama book), published by O'Reilly and Associates.


Dave

In reply to Re: Comparing files by davido
in thread Comparing files by dannyp

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