PHP Regex

 <?php

 //Accpet the http client request and generate response content.
 //As a demo, this function just send "PHP HTTP Server" to client.
 function handle_http_request($address, $port)
 {
     $max_backlog = 16;
     $res_content = "HTTP/1.1 200 OK
         Content-Length: 15
         Content-Type: text/plain; charset=UTF-8

         PHP HTTP Server";
     $res_len = strlen($res_content);

     //Create, bind and listen to socket
     if(($socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) === FALSE)
     {
         echo "Create socket failed!\n";
         exit;
     }   

     if((socket_bind($socket, $address, $port)) === FALSE)
     {
         echo "Bind socket failed!\n";
         exit;
     }

     if((socket_listen($socket, $max_backlog)) === FALSE)
     {
         echo "Listen to socket failed!\n";
         exit;
     }

     //Loop
     while(TRUE)
     {
         if(($accept_socket = socket_accept($socket)) === FALSE)
         {
             continue;
         }
         else
         {
             socket_write($accept_socket, $res_content, $res_len);
             socket_close($accept_socket);
         }
     }
 }

 //Run as daemon process.
 function run()
 {
     if(($pid1 = pcntl_fork()) === 0)
     //First child process
     {
         posix_setsid(); //Set first child process as the session leader.

         if(($pid2 = pcntl_fork()) === 0)
         //Second child process, which run as daemon.
         {
             //Replaced with your own domain or address.
             handle_http_request('www.codinglabs.org', 9999);
         }
         else
         {
             //First child process exit;
             exit;
         }
     }
     else
     {
         //Wait for first child process exit;
         pcntl_wait($status);
     }
 }

 //Entry point.
 run();

 ?>