	private function flushHeaders() {
		$file = null; 
		$line = null;
		if (headers_sent($file, $line)) {
			throw new \ErrorException('Response sent outside of n2n context', 
					0, E_USER_ERROR, $file, $line);
		}
		
		header('X-Powered-By: N2N/' . N2N::VERSION, false, $this->bufferedStatusCode);
		
		if ($this->bufferedHttpCacheControl !== null && $this->httpCachingEnabled) {
			$this->bufferedHttpCacheControl->applyHeaders($this);
		} else {
			$httpCacheControl = new HttpCacheControl();
			$httpCacheControl->applyHeaders($this);
		}
		
		while (!is_null($header = array_pop($this->bufferedHeaders))) {
			header($header->getHeaderStr(), $header->isReplace());
		}
	}
