static function ClearLog()
 {
     $bindlog = ctrl_options::GetSystemOption('bind_log');
     if (is_writable($bindlog)) {
         $log = $bindlog;
         if (file_exists($bindlog)) {
             $fp = fopen($log, 'w');
             fwrite($fp, '');
             fclose($fp);
         }
     } else {
         self::$notwritable = true;
     }
 }