Hmm.. the simplest form is something like 
$ perl -pi.bak -e's/foo/bar/' file1 file2 ..

[download]
Look for the documentation of the -p and -i switches in perldoc perlrun. In what context are you trying to do this?

Makeshifts last the longest.

In reply to Re: Replacing a string in a file by Aristotle
in thread Replacing a string in a file by Avi

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