leegao has written
seems to be a none programmer-related problem, PHP on a non-standalone environment have execution conditions made by the server itself, in this case, apache calls it via cgi or as a direct mod.
UDP's real name is the User-Datagram Protocol, often derisively known as the Unreliable Data Protocol, and this is without boast. CS2D and most modern game/streaming client uses several backtracking techniques to double check that the correct payload is received. In CS2D's case, both a server-id and a confirmation packet is sent with most packets (all except for the info requests for the latter). In php's case, the fact that the execution time is limited means that there's no possible way to double check the messages. So in certain cases, the PHP server will receive corrupted or incomplete messages. This is without fix unless you're willing to wait around for multiple packets to arrive.