I managed to remove this problem by closing the dir before throwing all these threads.

Hm. I tried that here and it didn't effect a cure reliably. It would sometimes (mostly), work with small numbers of files (threads), but if I asked it to run a couple of hundred threads it always failed during globals destruction.

But when I used a glob, the problem disappeared. (I'll have another go later to confirm my findings!)

As for how to debug it, the watchword with threads is pretty much always the same: simplify.

First I tried a non-threaded version. No trap. Then a one threaded. No trap. Then 10 threads--trap.

So then I tried simplifying the thread proc. Take out everything except 

sub threads {
    my ($msg, $peerAddr, $peerPort) = @_;
    sleep 1;
    return [1, $msg];
}

[download]

Still traps, so look outside. Replaced the while( readdir ) with while( <DATA> ) { and a list of files that caused a trap and the trap went away.

Put back the full thread proc and a larger DATA section, trap still didn't happen.

Put back the opendir/readdir/closedir. Trap returns.

Try glob. trap disappears again. Bingo!

Update: I just tried building the file list using opendir/readdir/closedir first, and then starting the threads again, and this time it worked fine. Maybe I missed that combination last night.

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^5: win32 threads problem by BrowserUk
in thread win32 threads problem by leonidlm

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