套接字没有绑定

Question

`我正在尝试逐步学习php中的socket编程。但我无法理解为什么我会看到这个错误：

•  Warning: socket_bind(): unable to bind address [10048]: Only one usage of each socket address (protocol/network address/port) is normally permitted. in D:\wamp\www\pl\mo.php on line 16
  

• 我曾尝试多次更改端口号但没有用。我一直看到同样的错误。

  set_time_limit(0);
  
  $ip = "127.0.0.1";
  $port = 123;
  
   // set the protocols
       if( !$socket = socket_create(AF_INET,SOCK_STREAM,0) ){
    echo "cant creat socket"    ;
  }
  
  echo "The socket's protocol info was set \n";
  
  // bind the socket
  if( !socket_bind($socket,$ip,$port) ){
  echo "can't bind socket";
  }
  ?>