my @closed = list_of_files();
  my @open = ();
  my $count = 0;
  while (1) {
    my $time = Time::HiRes::time();
    check_moved(\@open) if ($count % $CHECKMOVED) == 0;
    check_new(\@closed) if ($count % $CHECKNEW) == 0;
    check_read(\@open) if ($count % $CHECKREAD) == 0;
    ++$count;
    my $delay = $TICK - (Time::HiRes::time() - $time);
    Time::HiRes::sleep($delay) if $delay > 0;
  }