estoque

Need help on this guys. I'm working on a new project and I'm fairly new on socket connections. Background: I'm creating a PHP script that can receive and store new SMS messages from GSM modem via its API(TCP, request/response way). So far, the manufacturer told me that I should follow this flow on using the device's API: 1. GSM modem sends User Authentication message to Socket Server once a connection is made. 2. Socket Server sends a response. 3. Socket Server waits for incoming connections from GSM. This is my code as of the moment: <?php set_time_limit (0); // Set the ip and port we will listen on $address = '127.0.0.1'; $port = 8855; $sock = socket_create(AF_INET, SOCK_STREAM, 0); socket_bind($sock, $address, $port) or die('Could not bind to address'); socket_listen($sock); $client = socket_accept($sock); //Breakdown of received message from GSM modem, I needed the $ID as identifier on my response $length = bin2hex(socket_read($client, 4)); $ID = bin2hex(socket_read($client, 16)); $type = bin2hex(socket_read($client, 4)); $username = bin2hex(socket_read($client, 16)); $password = bin2hex(socket_read($client, 16)); //This is what I should send on the socket as a response $rlength=pack("H*", "00000001"); $rID=pack("H*", $ID); $rtype=pack("H*","00100000"); $rresult=pack("H*", "00"); $response=$rlength.$rID.$rtype.$rresult; //Write the response on the socket socket_write($client, $response, $strlen($response)); //After sending the data, I should wait for the GSM modem's incoming connection when a new SMS message is received. //Any insights what should I code below? socket_close($client); socket_close($sock); ?>