Hi I have the following code that creates workers processing a queue. The problem I have is when to undefine the queue. My only solution I found was to create an array to hold all threads that are idling. When the array count is equal the thread count I undefine the queue and join the threads. I am sure there is better / cleaner ways to do that.. Any help would be appreciated. 
sub pullDataFromDbWithDirectory {
    my $_dir = $_[0];

    if ($itemCount <= $maxNumberOfItems) {
        my @retval = grep { /^Dir|^File/ } qx($omnidb -filesystem $fil
+esystem  '$label'  -listdir '$_dir');

        foreach my $item (@retval) {
            $itemCount++;
            (my $filename = $item) =~ s/^File\s+|^Dir\s+|\n//g;
            my $file = "$_dir/$filename";
            push(@data,$file);

            if ($item =~ /^Dir/) {
                $worker->enqueue($file);
                print "Add $file to queue\n" if $debug;
            }
        }
    }
}

sub doOperation () {
    my $ithread = threads->tid();
    do {
       my $folder = $worker->dequeue();
       print "Read $folder from queue with thread $ithread\n" if $debu
+g;
       pullDataFromDbWithDirectory($folder);
   } while ($worker->pending());

   push(@IDLE_THREADS,$ithread);

}

[download]
This is the main section 
my @threads = map threads->create(\&doOperation), 1 .. $maxNumberOfPar
+allelJobs;
pullDataFromDbWithDirectory($directory);


sleep 0.01 while (scalar @IDLE_THREADS < $maxNumberOfParallelJobs);
$worker->enqueue((undef) x $maxNumberOfParallelJobs);
$_->join for @threads;

printData();

[download]

In reply to Proper undefine queue with multithreads by sanc

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