use strict;
use warnings;

use MCE::Mutex;
use MCE::Shared;

my $mutex = MCE::Mutex->new();
my $data  = MCE::Shared->array();

if ( ! defined ( my $pid = fork() ) ) {
   die "Cannot fork!: $!";
}
elsif ( $pid == 0 ) {
   # Child
   MCE::Shared->init();
   my $item;
   sleep 1;

   for ( my $i = 1; $i <= 10; $i++ ) {
      $mutex->lock();
      $item = $data->shift();
      $mutex->unlock();
      $item = '' if ( ! defined $item );

      print "Child: $item\n";
   }
}
else {
   # Parent
   for ( my $i = 1; $i <= 10; $i++ ) {
      $mutex->lock();
      $data->push($i);
      $mutex->unlock();

      print "Parent: ", join(" ", $data->vals()), "\n";
   }

   waitpid( $pid, 0 );
}