PHP Socket communication UDP communication example

//服务器信息
$server = 'udp://127.0.0.1:9998';
//消息结束符号
$msg_eof = "\n";
$socket = stream_socket_server($server, $errno, $errstr, STREAM_SERVER_BIND);
if (!$socket) {
  die("$errstr ($errno)");
}
do {
  //接收客户端发来的信息
  $inMsg = stream_socket_recvfrom($socket, 1024, 0, $peer);
  //服务端打印出相关信息
  echo "Client : $peer\n";
  echo "Receive : {$inMsg}";
  //给客户端发送信息
  $outMsg = substr($inMsg, 0, (strrpos($inMsg, $msg_eof))).' -- '.date("D M j H:i:s Y\r\n");
  stream_socket_sendto($socket, $outMsg, 0, $peer);
} while ($inMsg !== false);

function udpGet($sendMsg = '', $ip = '127.0.0.1', $port = '9998'){
  $handle = stream_socket_client("udp://{$ip}:{$port}", $errno, $errstr);
  if( !$handle ){
    die("ERROR: {$errno} - {$errstr}\n");
  }
  fwrite($handle, $sendMsg."\n");
  $result = fread($handle, 1024);
  fclose($handle);
  return $result;
}
$result = udpGet('Hello World');
echo $result;