static int php_sockop_flush(php_stream *stream)
{
#if 0
	php_netstream_data_t *sock = (php_netstream_data_t*)stream->abstract;
	return fsync(sock->socket);
#endif
	return 0;
}

The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.