change: 
$pid = open(ERROR, "$cmd 2>&1 1>/dev/null |");

[download]
to 
$pid = open(ERROR, "$cmd 1>/dev/null 2>&1 |");

[download]
I know that in Unix, putting them the wrong way around causes the same symptoms you are talking about.

In reply to Re: Sending STDERR to a filehandle by ozone
in thread Sending STDERR to a filehandle by Anonymous Monk

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