fetch_content(@urls);
  $pm->wait_all_children;

  ## Run when children are forked
  $pm->run_on_start(
          sub { my ($pid, $link) = @_;
                  $link =~ s/\s+$//;  

                  ## Count the pages fetched thus far
                  $pagecount++;
          }
  );

  ## Run when child processes complete
  $pm->run_on_finish(
          sub { my ($pid, $exit_code, $ident) = @_;
                  print "\n** $ident out of the pool ".
                        "with PID $pid and exit code:
                         $exit_code\n";
          }
  );
  
  ## Run when blocking/waiting for children
  $pm->run_on_wait(
          sub {
                  print "-"x74, "\n";
                  print "\n** Waiting for child ...\n";
                  print "-"x74, "\n";
          },
          0.1
  );

  ## Fetch the actual page and links  
  sub fetch_content {
        my @urls = @_;

        for my $link (@urls) {
                my $pid = $pm->start($link) and next;

                # fetch the page, extract the links
                # (all of the fetching/extraction works)

                $pm->finish;
        }
  }