note 108535 added to function.socket-create

It took some time to understand how one PHP process can communicate with another by means of unix udp sockets. Examples of 'server' and 'client' code are given below. Server is assumed to run before client starts. 'Server' code <?php if (!extension_loaded('sockets')) { die('The sockets extension is not loaded.'); } // create unix udp socket $socket = socket_create(AF_UNIX, SOCK_DGRAM, 0); if (!$socket) die('Unable to create AF_UNIX socket'); // same socket will be used in recv_from and send_to $server_side_sock = dirname(__FILE__)."/server.sock"; if (!socket_bind($socket, $server_side_sock)) die("Unable to bind to $server_side_sock"); while(1) // server never exits { // receive query if (!socket_set_block($socket)) die('Unable to set blocking mode for socket'); $buf = ''; $from = ''; echo "Ready to receive...\n"; // will block to wait client query $bytes_received = socket_recvfrom($socket, $buf, 65536, 0, $from); if ($bytes_received == -1) die('An error occured while receiving from the socket'); echo "Received $buf from $from\n"; $buf .= "->Response"; // process client query here // send response if (!socket_set_nonblock($socket)) die('Unable to set nonblocking mode for socket'); // client side socket filename is known from client request: $from $len = strlen($buf); $bytes_sent = socket_sendto($socket, $buf, $len, 0, $from); if ($bytes_sent == -1) die('An error occured while sending to the socket'); else if ($bytes_sent != $len) die($bytes_sent . ' bytes have been sent instead of the ' . $len . ' bytes expected'); echo "Request processed\n"; } ?> 'Client' code <?php if (!extension_loaded('sockets')) { die('The sockets extension is not loaded.'); } // create unix udp socket $socket = socket_create(AF_UNIX, SOCK_DGRAM, 0); if (!$socket) die('Unable to create AF_UNIX socket'); // same socket will be later used in recv_from // no binding is required if you wish only send and never receive $client_side_sock = dirname(__FILE__)."/client.sock"; if (!socket_bind($socket, $client_side_sock)) die("Unable to bind to $client_side_sock"); // use socket to send data if (!socket_set_nonblock($socket)) die('Unable to set nonblocking mode for socket'); // server side socket filename is known apriori $server_side_sock = dirname(__FILE__)."/server.sock"; $msg = "Message"; $len = strlen($msg); // at this point 'server' process must be running and bound to receive from serv.sock $bytes_sent = socket_sendto($socket, $msg, $len, 0, $server_side_sock); if ($bytes_sent == -1) die('An error occured while sending to the socket'); else if ($bytes_sent != $len) die($bytes_sent . ' bytes have been sent instead of the ' . $len . ' bytes expected'); // use socket to receive data if (!socket_set_block($socket)) die('Unable to set blocking mode for socket'); $buf = ''; $from = ''; // will block to wait server response $bytes_received = socket_recvfrom($socket, $buf, 65536, 0, $from); if ($bytes_received == -1) die('An error occured while receiving from the socket'); echo "Received $buf from $from\n"; // close socket and delete own .sock file socket_close($socket); unlink($client_side_sock); echo "Client exits\n"; ?> ---- Server IP: 69.147.83.197 Probable Submitter: 91.191.225.107 ---- Manual Page -- http://www.php.net/manual/en/function.socket-create.php Edit -- https://master.php.net/note/edit/108535 Del: integrated -- https://master.php.net/note/delete/108535/integrated Del: useless -- https://master.php.net/note/delete/108535/useless Del: bad code -- https://master.php.net/note/delete/108535/bad+code Del: spam -- https://master.php.net/note/delete/108535/spam Del: non-english -- https://master.php.net/note/delete/108535/non-english Del: in docs -- https://master.php.net/note/delete/108535/in+docs Del: other reasons-- https://master.php.net/note/delete/108535 Reject -- https://master.php.net/note/reject/108535 Search -- https://master.php.net/manage/user-notes.php