If you're doing this on a Unix-like operating system, or on Win32 with Cygwin, have a look at the diff(1) command. You'd probably be better off reading diffs and working with their output than reinventing the wheel. You might also look in CPAN for diff-related modules.

--
:wq

In reply to Re: Compare files and copy differences by FoxtrotUniform
in thread Compare files and copy differences by Kentdn

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