A far simpler way would be from the command line. A Bash script to do it would look like this... 
$ cd $1
$ perl -i -w script.pl *.$2

[download]
See perlrun for details on the command line switches. You can include an extension after -i and it will keep backups for you, as in -i.bak for instance.

In reply to Re: Opening, and editing multiple files? by quester
in thread Opening, and editing multiple files? by Anonymous Monk

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