private function isCurlException(RequestInterface $request, CurlHandle $handle, array $curl)
    {
        if (CURLM_OK == $curl['result'] || CURLM_CALL_MULTI_PERFORM == $curl['result']) {
            return false;
        }

        $handle->setErrorNo($curl['result']);
        $e = new CurlException(sprintf('[curl] %s: %s [url] %s',
            $handle->getErrorNo(), $handle->getError(), $handle->getUrl()));
        $e->setCurlHandle($handle)
            ->setRequest($request)
            ->setCurlInfo($handle->getInfo())
            ->setError($handle->getError(), $handle->getErrorNo());

        return $e;
    }