The File::Compare appears to be solely to tell you that there is a difference, not what the differences are. You might want to use something like Text::Diff to extract what the actual differences are between the files. (I haven't used either, but both the functions in the File::Compare say they just stop as soon as a line is different1. For Text::Diff, it implies it returns a string that's similar to the output off the linux diff command, so you could then write that string to your third file.

Aside: if you edit your post (How do I change/delete my post?) to include <code> tags (see also Perl Monks Approved HTML tags) around your program, it will make it easier for future readers of this thread to understand what you were asking, and provide more insight than I have.

1 edit: clarifying, only the compare_text specifies stopping at the first line that is different; but both only return whether the files are the same (0) or different (1), and not what the differences are.

In reply to Re: comparing any two text files and writing the difference to a third file by pryrt
in thread comparing any two text files and writing the difference to a third file by balanunni

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