if i ran the script with 10 threads i would get about 4-7 threads that would hang.

Quite possibly symptoms of the same problem on a multi-cpu system rather than my single cpu system?

You could try addressing the issue that moritz raised, by changing your loop to: 

while( my $left = $q->dequeue_nb ) {

[download]

And see if that helps any. If not, try generating a standalone demo of the problem (using ping) and post a perlbug report. Maybe whomever there fixed the problem for 5.10 will recognise the symptom and be able to offer a patch against 5.8.8?

Beyond that, I can't see any way of avoiding the bug, as it also affects piped opens. The alternative might be to use NET::SNMP to do whatever the executable your using is doing. Perhaps too painful to reproduce?

One thing that route does have going for it is a non-blocking mode that appears to work quite well, which mean that you could avoid using threads altogether.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^3: threads hang by BrowserUk
in thread threads hang by Ryszard

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