var stream = require('stream');
var util = require('util');		//tools

function ReadStream(){
	// 改变上下文
	stream.Readable.call(this);
}

util.inherits(ReadStream, stream.Readable);

ReadStream.prototype._read = function() {
	this.push('Hello ');
	this.push('I ');
	this.push('Love ');
	this.push("Scott's ");
	this.push('lessons\n');
	this.push(null);	//	代表push结束
};

function WritStream(){
	stream.Writable.call(this);
}

util.inherits(WritStream, stream.Writable);

WritStream.prototype._write = function(chunk, encode, cb) {
	console.log(chunk.toString());
	cb();
};

function TransformStream(){
	stream.Transform.call(this);	
}

util.inherits(TransformStream, stream.Transform);

TransformStream.prototype._transform = function(chunk, encode, cb) {
	this.push(chunk);
	cb();
};

TransformStream.prototype._flush = function(cb) {
	this.push('Oh Fuck!');
	cb();
}

var rs = new ReadStream();
var ws = new WritStream();
var ts = new TransformStream();

rs.pipe(ts).pipe(ws);

这个也是第一行不显示

//代码如下
var Readable = require('stream').Readable;
var Writable = require('stream').Writable;

// 实例化
var readStream = new Readable();
var writStream = new Writable();

readStream.push('Hello ');
readStream.push('I ');
readStream.push('Love ');
readStream.push("Scott's ");
readStream.push('lessons\n');
readStream.push(null);	//	代表push结束


writStream._write = function(chunk, encode, cb)
{
	console.log(chunk.toString());
	cb();
}

readStream.pipe(writStream);