2 $vw = $_SERVER["HTTP_VIEWPORT_WIDTH"];
3 $expected_vw = $_GET["viewport"];
5 if ((isset($expected_vw) && $vw == $expected_vw) ||
(isset($vw) && !isset($expected_vw))) {
6 $fn = fopen("compass.jpg", "r");
11 header("HTTP/1.1 417 Expectation failed");