www.greg-wright.co.uk

    if (file_exists($data_dir . '/dnscache')) {
        $fp = fopen($data_dir . '/dnscache', 'r');
    } else {
        $fp = false;
    }
    if ($fp) {
        flock($fp,LOCK_EX);
    } else {
       $fp = fopen($data_dir . '/dnscache', 'w+');
       fclose($fp);
       $fp = fopen($data_dir . '/dnscache', 'r');
       flock($fp,LOCK_EX);
    }
    $fp1=fopen($data_dir . '/dnscache', 'w+');