/**
  * Retrieve the underlaying resource.
  *
  * This method is called in response to stream_select().
  *
  * @param integer $cast_as Can be STREAM_CAST_FOR_SELECT when stream_select() is calling stream_cast() or STREAM_CAST_AS_STREAM when stream_cast() is called for other uses.
  * @return resource Should return the underlying stream resource used by the wrapper, or FALSE.
  */
 public function stream_cast($cast_as)
 {
     return $this->streamWrapper->cast($cast_as);
 }