Creating a socket based chat application in php

<form action="UDPsrvr.php" method="post">
            Name :<input type="text" name="data"><br>
            <input type="submit" value="Send" name="subt"/>
        </form>
    <?php


error_reporting(E_ALL | E_STRICT);

$socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
socket_bind($socket, '127.0.0.1', 1223);

$from = '';
$port = 0;
socket_recvfrom($socket, $buf, 12, 0, $from, $port);

//echo "Received $buf from remote address $from and remote port $port" . PHP_EOL;

echo "<textarea name='n'>".$buf."</textarea>";

if($_POST['subt']){
  $data=  $_POST['data'];
   socket_sendto($sock, $data, $len, 0, '127.0.0.1', 1223);
}
   ?>

  <form action="UDPclint.php" method="post">
        Msg  :) <input type="text" name="nm"><br>
        <input  type="submit" value="Send" name="sub"/>
    </form>
<?php
  if(isset($_POST['sub'])) {
     $sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);


$msg = $_POST['nm'];
$len = strlen($msg);

socket_sendto($sock, $msg, $len, 0, '127.0.0.1', 1223);
socket_close($sock);
  }

?>