stream

var fs = require('fs')
var readStream = fs.createReadStream('logo.png')
var n = 0

readStream
    .on('data',function (chunk) {
        n++
        console.log('data emit')
        console.log(Buffer.isBuffer(chunk))
        readStream.pause()
        console.log('data pause' )
        setTimeout(function () {
            console.log('data pause end')
            readStream.resume()
        },3000)
    })
    .on('readable',function () {
        console.log('data readable')
    })
    .on('end',function () {
        console.log(n)
        console.log('end')
    })
    .on('close',function () {
        console.log('data close');
    })
    .on('error',function (e) {
        console.log('eror' + e)
    })


//fs.createReadStream('qd1.mp4').pipe(fs.createWriteStream('1-qd1.mp4'))