Results for say it out translation from Korean to English

예 1. compute the md5 digest and hmac and print it out as hex
this extension has no resource types defined.

you do not need to pass every array to socket_select(). you can leave it out and use an empty array or null instead. also do not forget that those arrays are passed by reference and will be modified after socket_select() returns.
/* prepare the read array * / $read = array( $socket1, $socket2); if (false === ($num_changed_sockets = socket_select($read, $write = null, $except = null, 0))) {/ * error handling * / else if ($num_changed_sockets 0) {/ * at least at one of the sockets something interesting happened * /}