I'd say that objection 2 is more obviously resolved using either IPC::Open3 or IPC::Run3. The other two arguments remain, unless of course there is no Perl equivalent, so e.g. the unix command 
comm [-123] file1 file2

[download]
if used repeatedly should be replaced with a handrolled Perl equivalent to prevent process creation overheads, or else provided your expectations are Unix only and non-repeating you could still allow the odd shelling out with IPC.
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^M Free your mind!

In reply to Re:Re-write shell in perl by Moron
in thread Re-write shell in perl by andreas1234567

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