function request_by_curl($remote_server, $post_string)
{
 $ch = curl_init();
 curl_setopt($ch, CURLOPT_URL, $remote_server);
 curl_setopt($ch, CURLOPT_POSTFIELDS,   $post_string);
 curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
 curl_setopt($ch, CURLOPT_USERAGENT, "Mozilla/5.0 (Linux; U; Android 2.3.7; zh-cn; c8650 Build/GWK74) AppleWebKit/533.1 (KHTML, like Gecko)Version/4.0 MQQBrowser/4.5 Mobile Safari/533.1s");
 $data = curl_exec($ch);
 curl_close($ch);
 return $data;
} 

$form="lang=C&private=True&submit=Submit&run=True&code=main(){printf(\"xunda\");}";
$url="http://codepad.org/";
$data=request_by_curl($url,$form);
echo $data;
echo "xunda";