/**
  * get size from URL.
  *
  * @param $durl
  * @return int
  */
 function getRemoteSize($durl)
 {
     global $instanceSimpleHTTP;
     // initialize if needed
     if (!isset($instanceSimpleHTTP)) {
         SimpleHTTP::initialize();
     }
     // call instance-method
     return $instanceSimpleHTTP->instance_getRemoteSize($durl);
 }