```
// node_modules/
socket.io/lib/index.js// nodejs add this route in its codes
Server.prototype.attachServe = function(srv){
debug('attaching client serving req handler');
var url = this._path + '/socket.io.js';
var evs = srv.listeners('request').slice(0);
var self = this;
srv.removeAllListeners('request');
srv.on('request', function(req, res) {
if (0 == req.url.indexOf(url)) {
self.serve(req, res);
} else {
for (var i = 0; i < evs.length; i++) {
evs[i].call(srv, req, res);
}
}
});
};
```