I use Perl for a lot of quick file-munging (and golf :-), so I've found it very useful to be familiar with the command line options as described in perlrun. The -n, -p, and -i options can be particularly handy if you're just running through files doing something to each line. For example, you can replace "foo" with "bar" in every .txt file in a directory with this one-liner:

perl -pi -e 's/foo/bar/g' dir/*.txt
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Very simple, but very powerful. Of course you can do more complex things with this as well.

-- Mike

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just,my${.02}