该程序使用pipe()流类提供的功能使用可读和可写流复制文件
// 需要文件系统模块
var fs = require('fs');
/*
Create readable stream to file in current directory named 'node.txt'
Use utf8 encoding
Read the data in 16-kilobyte chunks
*/
var readable = fs.createReadStream(__dirname + '/node.txt', { encoding: 'utf8', highWaterMark: 16 * 1024 });
// 创建可写流
var writable = fs.createWriteStream(__dirname + '/nodePipe.txt');
// 使用管道将可读复制为可写
readable.pipe(writable);