If there's no output from the pipe open, there'll be nothing read from PROCS, so your loop won't execute. You could set a flag:

my $output;
while (<PROCS>)
{
    $output++;
    # do something else
}

print "Couldn't find $process\n" unless $output;

[download]

The a Proc::ProcessTable module might be another approach.

Update: I forgot to mention that your loop will not execute if a line evaluating to false in boolean context is read — that may not be a problem in this case, but it's worth remembering.

In reply to Re: undefined question by chromatic
in thread undefined question by Anonymous Monk

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