I wasn't thinking straight -- forget my comment about waitpid() which you would need if you did your own fork/exec. You don't need it with backticks. Basically backticks sets $? so you can check it directly (by using this code ripped from 'perldoc -f system'...

$exit_value  = $? >> 8;
$signal_num  = $? & 127;
$dumped_core = $? & 128;
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bluto