Node.js Stream（流）

var stream = require("stream"); 
var EventEmitter = require("events").EventEmitter; 

console.log(new stream.Stream() instanceof EventEmitter); // true 
console.log(new stream.Readable({}) instanceof stream.Stream); // true 
console.log(new stream.Writable({}) instanceof stream.Stream); // true 
console.log(new stream.Duplex({}) instanceof stream.Stream); // true 
console.log(new stream.Transform({}) instanceof stream.Stream); // true 

var fs = require("fs"); 
// Create readable stream 
var readableStream = fs.createReadStream("./a.js"); 
// Pipe it to stdout 
readableStream.pipe(process.stdout); 

var fs = require("fs"); 
var gzip = require("zlib").createGzip(); 

var inp = fs.createReadStream("a.js"); 
var out = fs.createWriteStream("a.js.gz"); 

// Pipe chain 
inp.pipe(gzip).pipe(out);