Let Google be your friend!
Found this (did not test it - will leave that to you) with
the following search: "calculating directory size perl"

At following url:

http://bytes.com/topic/perl/answers/603354-calculate-size-all-files-directory

Take a look at "docsnyder's" post

In reply to Re: Fastest way to calculate directory size in linux by mr_magoo
in thread Fastest way to calculate directory size in linux by Anonymous Monk

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