Use the Unix program "diff". It's designed for this sort of thing.

It does depend on the files being in the same order each time, so you might have to sort them first.

Fortunately there is a Unix command called "sort" which can probably do that for you.

____________________
Jeremy
I didn't believe in evil until I dated it.

In reply to Re: How to process two files of over a million lines for changes by jepri
in thread How to process two files of over a million lines for changes by richard5mith

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