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Avoid running Node.js as PID 1 under Docker images

Turns out that Node.js cannot receive signals and handle them appropriately (if it runs as PID 1). By signals, I mean kernel signals like SIGTERM, SIGINT, etc.

The following code wouldn’t work at all if you run Node.js as PID 1:

process.on('SIGTERM', function onSigterm() {
  // do the cleaning job, but it wouldn't
  process.exit(0);
});

As a result, you will get a zombie process that will be terminated forcefully via SIGKILL signal, meaning that your “clean up” code will not be called at all.

So what, you might say. I’ll describe a real case.

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Bootstrap your terminal environment in MacOS with a single Bash script

How often do you face the issue with configuring your development environment? How often do you configure your terminal? Did you install Command Line Tools? What about Homebrew, don’t you forget to install it? Maybe you forgot about some cool plugin for your shell and can’t find it?

This is the problem I am usually faced with clean MacOS install, so maybe you too.

Some error in the terminal, oh, I forgot to install X…
How did that work before? Oh, I had plugin Y, but I don’t remember its name…
Who enjoys remembering all the fishy commands? I don’t…
Burn out my own eyes with a default theme and colors? No, thanks…
Navigating through a plugin repository of your shell to find out all plugins you had again? Haha, nope…

In case you just want to check the script, here is the link – https://github.com/ghaiklor/iterm-fish-fisher-osx

Further content is the history, my motives, while creating the script.

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How to implement a second stage boot loader?

Last time, we created a working boot sector, the BIOS can find with the help of magic numbers. You can read more about it here (if you didn’t, I highly recommend doing that now, as you may miss some important details).

The question here is “Why do we need a second stage boot loader?”. We can implement all of it in the boot sector, using Assembly, so… why?

The problem is… size limits. You can’t store over 512 bytes of code in the boot sector, so if you want to make a super-duper boot loader (like GRUB or similar) you need to store all of it somewhere else, but not in the boot sector itself.

And that is one of reasons, we need to have a second stage boot loader.

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How Node.js requires native shared objects

Recently, I faced an issue with requiring native bindings in JavaScript code, so I researched it. If you ever used commands, like require(‘my_module.node’) but don’t know how they work from JavaScript perspective — this article is for you.

What is .node files and why do we need them?

Sometimes, we are using npm packages that have native bindings for their purposes. Sometimes, we are building our own C++ code to extend the Node.js functionality for our own purposes. In both cases, we need to build an external native code to an object that can be usable by Node.js.

And that’s what .node files are for. .node files are dynamically shared objects that Node.js can load to its environment. Making an analogy here, I would say that .node files are very similar to .dll or .so files.

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JavaScript is not so bad, as everyone said

A lot of times, I heard how developers from different companies, which are writing in Python, C++, Java and other programming languages, say that JavaScript is crap. This bothered me for a while, so, at some point, I wrote this article to share my thoughts with you about JavaScript and it’s bad and, maybe, good parts.

Though, first, I would like to introduce myself a little, so you can decide, if it’s worth it to listen to me or if I’m just another blind JavaScript evangelist that knows none other language (choose your).

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ASCII presentations in the terminal are real

Today, I want to tell you about one interesting project called Kittik. The main idea behind this project is to create and show presentations that support shapes, animations, embedding code, etc. right in your terminal. Can you believe this? Ok, let’s dig.

Why do we need this?

We are all hackers, if you are a geek, if you want to impress your auditory with amazing slides in your speech or just for fun — there are many uses you can imagine.

Personally, I’m using it in some of my speeches, light-talks. And, you know, it looks impressive. Let me show you a simple presentation with three slides. It’s not so beautiful as you can create it, but the main purpose of a demo below is to show you all the shapes\animations, you can use, in few slides.

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Strange bug ever in V8

Recently, I find out about a strange bug in V8. Everyone is discussing it in Twitter, Facebook, Gitter and other social networks. So, I will try to explain it.

To my knowledge, it happens in the latest stable version of Google Chrome (my version is 51.0.2704.103).

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How to contribute in Node.js?

Some of you want to or thought about contributing into Node.js core but don’t know how to do it or don’t have enough confidence. Well, I’ll try to help you out with that.

I am an outside collaborator in Node.js and sometimes I look into issues and take some. Also, I already have a few pull requests successfully landed into Node.js core, so I will tell you about my experience.

Let’s start with running it locally.

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