Linux is an open-source operating system (OS) used on many platforms. It's prevalent on servers and supercomputers. However, Linux is versatile and can run on desktops, laptops, embedded devices, mobile devices, and more.
First introduced by Linus Torvalds, the OS has been around since 1991. It is a free alternative to other systems like Unix and Minix. Today there are many different flavors of Linux that have emerged over the years. These include RedHat Enterprise Linux (RHEL), Debian, Ubuntu, Gentoo, and many more.
When you hear the term Linux, it may conjure up images of a geeky dude with long hair and a t-shirt that says, “Linux is my religion.” Well, if you're thinking about becoming a programmer or computer scientist, that may be you.
There's no single creator or designer behind Linux today. Instead, it's an open-source OS modified and released by different programmers over time. This ecosystem stands in distinct contrast with Windows OS, over which Microsoft holds tight control.
Basic Concepts of Linux Programming
All distributions of Linux revolve around a kernel. The kernel is the OS's core, like a road's foundation. However, while the kernel is vital, you need additional software on top to make it useful. That software is known as the “overlay.”
The Linux kernel includes a set of commands and programs that allow you to control your device from the command line. Some examples of Linux commands include:
- bash – The default shell (command interface) for most Linux distributions.
- grep – A utility for searching text files for patterns.
- sudo – Prefaces a command that the OS should run an administrator.
Most Linux commands haven’t changed much over the years. While some variations exist on different Linux distributions, most are similar in concept. The Linux community also has a strong reputation for being inclusive, so it's easy for beginners to find others who will help them learn how to code.
Scripting in Linux
Learning to script in Linux is essential for any system administrator, developer, or software engineer. It's the only way to automate repetitive tasks and make your life easier. However, while you can use Linux scripts to automate tasks, it is essential to understand that none of them are as powerful as an actual programming language.
The Linux shell is a command-line interpreter that enables you to run one or more commands in succession. It acts like a rudimentary programming language allowing you to create shell scripts.
Shell scripts are plain text files containing a list of commands. You can write these scripts in any text editor, such as vim or nano, and then execute them by passing the filename as an argument to the shell. When you run a script, it will execute each line sequentially, as if you had entered those lines at the command prompt.
Here are some beginner basics for Linux commands and scripting;
- Hackr.io offers a list of the top 25 Basic Linux Commands for beginners.
- Learn Shell provides simple Linux shell tutorials and even an interface for you to test the skills you pick up.
- For a more comprehensive session on shell scripting, join the Learning Bash Scripting course on Linkedin.
Why Choose Linux for Programming?
You might be wondering what the point of learning Linux programming is. After all, you can use many other applications to build your applications. The first point of note is that Linux is free and open-source software. That makes it readily available to anyone at no retail cost.
Beyond that, the characteristics of Linux and its applications allow it to occupy a vital space in specific industries or use cases.
Linux supports many different languages, so switching over could be the right move if you're already familiar with one but want an extra challenge. Some of these languages have similar roots, so making a switch could be relatively painless.
In addition, these days, there are some tools like Docker containers where developers can write their code using any language they want regardless of whether or not the system itself supports it.
Note: Linux programming can mean different things. For example, you can choose to work on the Linux kernel, create kernel modules., or build Linux-based applications.
Linux Kernel Development
The Linux kernel is a core component of the Linux operating system that handles all of the system's tasks. It also handles input/output (I/O) requests, communications with devices like hard drives and network cards, file system access, memory management, process scheduling, and more.
The kernel acts as an intermediary between applications running on your computer and the hardware they use to do their work. It provides an interface for communication between these different parts, allowing them to work together smoothly.
Developing Linux Kernel Modules
Kernel modules are a type of kernel extension that can be loaded and unloaded at runtime. They consist of self-contained pieces of code that perform specific tasks, such as accessing hardware devices or implementing network protocols.
Generally speaking, there are two categories of Linux kernel modules: statically compiled and dynamically linked.
In the former case, the module is compiled into the kernel image when building it from the source; in the latter case (as with most applications), only an object file is included as part of the kernel build process. However, you must compile both kinds against a given version of Linux's Application Binary Interface (ABI) to work correctly.
Developing Applications For Linux
Linux is an excellent platform for developing applications because of its flexibility and scalability. It works on multiple platforms such as desktops, laptops, and servers. So if you have an idea or are working on something requiring portability across all systems, this is your best bet.
Linux is also an excellent platform for developing applications in terms of security and stability. It comes with high-quality open source software (OSS), ensuring that few bugs creep into your program while running it on Linux-based systems like Android phones and tablets or Raspberry Pi boards.
Careers in Linux Programming
Thanks to its popularity, there are many jobs in Linux programming. It’s a de facto standard in some industries and applications. For example, most servers will run on Linux. However, did you know that even mobile devices rely highly on Linux as the base?
Linux programmers are also crucial in niche industries like aerospace and defense, automotive, government, finance, healthcare, and many others.
If you’re considering a job in Linux programming, here are some sites available;
Indeed – This job aggregation website covers placement roles worldwide. You can find contract, freelance, or full-time positions at many companies. You'll find specialist Linux roles like Kernel Developer, JNet programmer, DevOps Engineer, or even Linux Server Engineer.
Dice – This recruitment platform leans towards the IT sector, and many roles are available for Linux programmers. You can join companies looking for Linux Software Engineers, Embedded Linux Developers, Python/Perl Programmers, and more.
Linux Foundation – Hardcore Linux fans can try to apply for work at the Linux Foundation. They’re always looking for talented people and currently need Lead Software Engineers, Data Engineers, Security Researchers, and more. There are also a fair number of non-programming roles available for Linux enthusiasts.
Linux and Linux Programming Resources
There are many resources for you to get help or learn more about Linux, various compatible programming languages, or even discuss problems with community members. These can cover a broad scope;
Download Linux Distributions
Linux Documentation and News
- The Linux Documentation Project is an effort to provide quality documentation for the GNU operating system. It aims to help users set up and maintain their computers under GNU/Linux or any of its variants (such as BSD).
- Linux Weekly News (LWN) is a weekly publication focusing on topics related to free software projects such as the kernel, utilities, device drivers, and more. It covers all aspects of building and maintaining Linux projects from a developer's point of view.
- 9to5 Linux is a relatively new blog that’s all about Linux. It brings the latest updates on everything Linux-related from distribution updates to Linux-specific tools.
Linux Communities and Forums
- The Linux Community Forum
- Spiceworks Linux Forum
- r/Linux on Reddit
- Linux Questions Forum
- Open Source Forum on StackExchange
Formal Linux & Linux Programming Courses
- Udemy – Here, you’ll find many Linux-specific courses, including several programming languages like Python, Perl, and more. Lessons are in video format, available on-demand, and include assignments and certificates of completion.
- Coursera – Like Udemy, Coursera provides comprehensive learning courses for various Linux disciples. You can learn everything from Linux fundamentals to Linux Private Cloud Administration.
- edX – Perhaps the most formal learning option, edX brings courses from over 160 member universities onto a single platform. Notable names include MIT, Harvard, and Boston University. You’ll find everything from professional certificates to Master’s degrees on edX.
Programming is a skill that transcends platforms, so the more programming you know, the better. Many of the most popular programming languages in use today are for Linux — and many of them are open source.
Learning the basics of programming is often more manageable when you can put it into context and see what problems it solves. Many of the resources above include tutorials on using your newly acquired knowledge.
The best way to learn any programming language is by doing it yourself. You will make mistakes in the beginning, but with time and practice, your skills will improve.