节点。JS -简单的套接字。IO例子不工作。获取调试——服务于静态内容/socket.io。js(Mac OSX / Localhost)

I just began with node.js a few days ago and I'm know trying to use socket.io module. But it is not working as I was expecting. The example I am trying to reproduce is this one : I just began with node.js a few days ago and I'