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var wait = require('waitgroup')
var fs = require('fs')

var wg = new wait

var list = ['file1.txt','file2.txt','file3.txt','file4.txt']

list.forEach(function(val) {
  wg.add()
  fs.readFile(val,{"encoding":"UTF-8"},function(e,data) {

retrohacker

var wait = require('waitgroup')
var fs = require('fs')

var wg = new wait

var list = ['file1.txt','file2.txt','file3.txt','file4.txt']

list.forEach(function(val) {
  wg.add()
  fs.readFile(val,{"encoding":"UTF-8"},function(e,data) {

retrohacker

var tar = require('tar')
var fstream = require('fstream')

function buildTar() {
  var converter = tar.Pack()
  var tarball = fstream.
    Writer({path:"./docker.tar",mode:755})
  converter.pipe(tarball)
  fstream
    .Reader("./")

retrohacker

#! /bin/sh
### BEGIN INIT INFO
# Provides:          helloInit
# Required-Start:    $remote_fs $syslog $network $portmap $time $localfs $named
# Required-Stop:     $remote_fs $syslog $network $portmap $time $localfs $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: A simple webserver demonstrating a node.js init script
# Description:       This shows the best way to construct a node.js init script
#                    It implements the best practices described in

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#! /bin/sh
### BEGIN INIT INFO
# Provides:          nodejs
# Required-Start:    $remote_fs $syslog $network $portmap $time $localfs $named
# Required-Stop:     $remote_fs $syslog $network $portmap $time $localfs $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: A simple webserver demonstrating a node.js init script
# Description:       This shows the best way to construct a node.js init script
#                    It implements the best practices described in

retrohacker

Error Handling

There are two different ways to handle errors in JavaScript. You can treat them as variables, or throw them. Both have their use cases, and you can convert back and forth between them using design patterns. Lets take a look at how each behave.

Try-Catch

If you are coming from another language, you are probably already familiar with try catch. Here is a basic example:

function trycatch() {

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/*
same file name, two different files.
*/

var fs = require('fs')

var file = './test.js'

var test = require(file)()

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{
  "/etc/annvix-release" : ["Annvix"],
  "/etc/arch-release" : ["Arch Linux"],
  "/etc/arklinux-release" : ["Arklinux"],
  "/etc/aurox-release" : ["Aurox Linux"],
  "/etc/blackcat-release" : ["BlackCat"],
  "/etc/cobalt-release" : ["Cobalt"],
  "/etc/lsb-release" : ["Chakra","IYCC","Linux Mint","Ubuntu Linux"],
  "/etc/conectiva-release" : ["Conectiva"],
  "/etc/debian_version" : ["Debian"],

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FROM ubuntu:trusty

# Setup sane dev environment
RUN apt-get update
RUN apt-get upgrade -y --force-yes
RUN apt-get install openssh-server -y --force-yes
RUN apt-get install sudo -y --force-yes

# Setup user ns w/ ssh keys
RUN mkdir /home/user

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function oops(y) {
	return [arguments, function () {return y}]
};
vals=oops(2);
y1=vals[1]();
vals[0][0]=3; // change "y"
y2=vals[1]();
// varies depending on strict mode or not
[y1,y2]