Dear Perl Monks,

my Perl program starts some threads that execute an external tool that I have to collect output from (STDOUT and STDERR). I'm using open3 from the IPC::Open3 package to start the child process and connect to its STDOUT and STDERR. Due to the tool manufacturer's somewhat weird idea of what an API is I have to execute that tool some hundred times per run.

Most of the time everything is fine but in some cases the open3 call blocks: It neither throws an exception nor returns. Yes, it's the open3 call itself and not the usual blocking problems with this function (I have solved them using select, sysread, and friends).

This is how I have implemented the call:

my $pid;
eval {
    $pid = open3(undef, \*CHLDOUT, \*CHLDERR, @$cmd);
};
if ($@) {
    ...
}

[download]

My Perl 5.8.9 (native 64 bit compilation) program runs on Solaris 10.

Do you have an idea what can make open3 hang/block and on how to continue debugging?

Thanks for your help and best regards,

Stephan

In reply to open3 hangs by stephan_a

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