I think you've cut this a little too deep for publication. There is a disagreement between open and diamond about the name of the filehandle. Furthermore, open is missing its third argument. Your example dies from syntax error. Aside from that, your code could be paraphrased as 

{
    local $/;
    open my $first_child, '-|', $cmd
      and $lines = <$first_child>;
        or do {
            # forky stuff
        }
}

[download]
If you get multiple children, it is because the open call fails.

Check whether each child uses huge hashes or arrays. Memory pressure is the likeliest cause of noticible slowdowns. Often, the cure is to rewrite the input handling.

After Compline,
Zaxo

In reply to Re: Code and Process Efficency by Zaxo
in thread Code and Process Efficency by mcogan1966

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