#!/usr/bin/perl

# Based on Parallel::ForkManager + IPC::Shareable by zentara.
# Found here: http://www.perlmonks.org/?node_id=1104697

use strict;
use Parallel::ForkManager;
use MCE::Mutex;
use MCE::Shared;

my $mutex = MCE::Mutex->new();
my $parent_share = tie my %final_parent_hash, 'MCE::Shared';

my $fork_manager = new Parallel::ForkManager(5);
   $fork_manager->set_waitpid_blocking_sleep(0);

foreach my $child ( 1 .. 10 ) {
    my $pid = $fork_manager->start($child) and next;

    # Optional, to have the shared-manager assign a data channel.
    # Helpful when involving heavy IPC usage, not the case here.
    # Increase 20 to 2000 to see perf-increase from calling ->init.
    MCE::Shared->init();

    for my $id ( 1 .. 20 ) {
        my $key = $child . '-' . $id;
      # $mutex->lock; # mutex not necessary when storing unique keys
      # $parent_share->set($key => qq{|Kid $child pushed $id}); # OO
        $final_parent_hash{$key} = qq{|Kid $child pushed $id};
      # $mutex->unlock;
    }

    $fork_manager->finish($child);
}

print "Waiting for Children...\n";
$fork_manager->wait_all_children;

foreach my $child ( 1 .. 10 ) {
    for my $id ( 1 .. 20 ) {
        my $key = $child . '-' . $id;
        if (! exists $final_parent_hash{$key} ) {
            print "Missing data for Kid $child , data $id\n";
        }
        else {
            print "$key = $final_parent_hash{$key}\n";
        }
    }
}