#snipped
if (my $pid=fork())
  {
    $|=; # Set auto-flush.
    print "Status: 302 Moved Temporarily\n";
    print "Location: asynctest.pl?c=$pid\n\n";
    close STDOUT;
    exit;
  }
  else
  {
    # We don't really need the PID file, but
    # daemonize() complains if you don't provide it,
    # despite the manpage saying it's optional.
    my $pidfile="/var/tmp/async$$.pid";
    my @current_user=getpwuid($<);
    daemonize($current_user[2],$current_user[3],$pidfile);
    sleep(20);
    unlink($pidfile); # otherwise it doesn't go away
    exit;
  }