It seems to me that there should be a problem--thr1 could be sitting their idle while thr0->join is blocking--but I don't know how you can see that problem in the output.

If it will work for you, you don't need to create new threads. You can just use the same two threads over and over:

use strict;
use warnings;
use 5.010;

use threads;
use threads::shared;
use Thread::Queue;

my $q : shared;
$q = Thread::Queue->new;    #a Queue is thread safe, which means 
                            #threads can read from it without
                            #interfering with each other.

my @files = (
    'file1',
    'file2',
    'file3',
    'file4',
    'file5',
);


my $thread_count = 2;
my @threads;

for (1 .. $thread_count) {
    my $thread_name = "thread$_";
    push @threads, threads->create(\&do_stuff, $thread_name);
}

$q->enqueue(@files); #...and the starting gun sounds!

for (1 .. $thread_count) {
    $q->enqueue("END_OF_QUEUE");
}

for my $thr (@threads) {
    $thr->join();
}



sub do_stuff {
    my $thr_name = shift;

    while ( (my $file = $q->dequeue) ne "END_OF_QUEUE" ) {

        #$q->dequeue() blocks until there is something to retrieve
        #from the queue.

        say "$thr_name is opening file: $file";

        #doing some work:
        sleep int(rand 4);

        say "$thr_name is is done with: $file";
    }
}


--output:--
thread1 is opening file: file1
thread2 is opening file: file2
thread2 is is done with: file2
thread2 is opening file: file3
thread1 is is done with: file1
thread1 is opening file: file4
thread2 is is done with: file3
thread2 is opening file: file5
thread2 is is done with: file5
thread1 is is done with: file4

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In reply to Re: wait for threads to end in parallel by 7stud
in thread wait for threads to end in parallel by pmarcoen

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