I second dasgar's answer, especially the first paragraph. That said, I have compressed things using something like the following, which would compress all .txt files in current and subdirs into target.zip: 
...
use Data::Dumper;
...
my @cmd = (
    'c:\Program Files\7-Zip\7z.exe',
    'a', '-mx9', '-r', 
    'target.zip',
    '*.txt',
    );
print 'about to execute: ', Dumper \@cmd;
system @cmd;

[download]
The 7zip man page is not on their home page, but over there you can have a glance.

In reply to Re^3: 7zip a folder by soonix
in thread 7zip a folder by ytjPerl

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