Hi there. First, there's no reason not to use 
use warnings;
use strict;

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For your problem: You might want to read up the perldoc of system, where the following is statet "Return value of -1 indicates a failure to start the program (inspect $! for the reason)."
Ordinary morality is for ordinary people. -- Aleister Crowley

In reply to Re: system calls by phaylon
in thread system calls by Anonymous Monk

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