var fs= require('fs');

//异步读取文件
fs.readFile('app.js','utf-8',function(err,data){
	if(err){
		console.error(err);
	}else{
		console.log(data);
	}
});
console.log("Ending ..");

var fs= require('fs');
//同步读取文件
data = fs.readFileSync('app.js','utf-8');
console.log(data);
console.log("Ending ..");

var EventEmitter = require('events').EventEmitter;
var event = new EventEmitter();

//注册some event 事件
event.on('some_event',function(){

	console.log('some event occured.');
});

setTimeout(function(){
//发送一个some_event 事件
event.emit('some_event');
},1000);