Linux Coding & Programming The Complete Manual -julkaisun Issue 1 -irtonumeron sisällysluettelo

Say Hello to Linux The Best Linux Distributions The Best Linux Distributions There are lots of versions of Linux available, known as Distributions. Each has a different ethos and approach. Here are five great distributions to try and where you can get them. GOING LINUX The installation process for most distributions is similar. You download a disk image from the website and burn it to an optical disk or create a USB Flash Drive installer. Just be careful to get the right distribution for your hardware and read the instructions carefully. LINUX MINT By far the most popular Linux distro (distribution) is Linux Mint. Mint began life back in 2006, as an alternative to the then most popular distro, Ubuntu. Although based on Ubuntu’s Long Term Support build, Linux Mint took…

Say Hello to Linux Which Distro? Which Distro? Up to now we’ve looked mainly at Linux Mint but there are other Linux distributions out there to try. In truth there are thousands of Linux distros available to download and install, so which one should you decide on to use? DISTRO HOPPING Distro hopping is a term used by the community for people who never stick to a single distribution. Instead, they hop from one to the other and back again, testing each, using them, then moving on to another or a newly released distro. There’s nothing wrong with distro hopping, as it’s a good way to get to grips with what’s out there and discover the elements of one distro over another that may or may not appeal to your…

Getting Started with Linux Installing Linux on a PC Installing Linux on a PC Most Linux distros come as a Live Environment. This means you can boot into an actual, fully-working distro straight from the DVD or USB that you just created. Let’s see how that works and how you go about installing Linux from there. UEFI BIOS The Unified Extensible Firmware Interface (UEFI) is used to identify hardware and protect a PC during its boot-up process. It replaces the traditional BIOS but can cause issues when installing Linux. STEP 1 Insert your DVD or USB flash drive into your PC and, if you haven’t already, shutdown Windows. In this instance we’re using the USB boot media but the process is virtually identical. Start the PC and when prompted press…

Index Getting to Know Linux Getting to Know Linux “Anyone can build a fast processor. The trick is to build a fast system.”– Seymour Cray (Electrical Engineer, and designer/founder of Cray Supercomputers) We’ve used Linux Mint as a guideline here, as it’s an easy to use distro and perfect for former Windows users. It’s also one of the most developed and well documented Linux distros as well as having some fantastic configuration options. In this section, we introduce the Linux Mint Cinnamon Menu and Desktop Environment, how it works and what you can do to customise it. Want to create another user or even discover how to become anonymous online? Then read on.…

Getting to Know Linux 10 Things to do After Installing Linux Mint 10 Things to do After Installing Linux Mint Linux Mint is a polished distro out of the box but, as with most Linux distros, there are some tweaks that can be applied to improve the way it works. Although these are Mint-specific tweaks, most can be applied to other distros. LINUX TWEAKS Some of these post-installation actions are highly recommended, while others are just handy additions and simply tweak the system or add a customisation. STEP 1 The first, and most important, post-installation action is to update the system. Click on the shield icon in the Panel, found at the bottom right of the desktop next to the time and date. This launches the Update Manager. STEP 2…

Getting to Know Linux Customising the Desktop Customising the Desktop Customising the operating system desktop is one way to make it your own: a personalised workspace that is there to help you work, inspire you or feature the company logo. Whatever your reasons for having your own desktop, here’s how it’s done. YOUR DESKTOP Linux is probably one of the customisable operating systems there is. With just a few tweaks, one or two extras installed and some imagination, you can create something incredible. STEP 1 The first aspect of desktop customisation is to change the wallpaper. Right-click the desktop and choose Change Desktop Background. This opens the Backgrounds app in Linux Mint; remember, other distros may present their background, wallpaper selection tools differently. STEP 2 More recent versions of Linux…

Using the Terminal Basics of the Terminal Basics of the Terminal Most operating systems use two kinds of interface, the GUI, which is the desktop that Windows, macOS and Linux Mint boot into and the command line. While modern operating systems shy away from the command line, Mint uses the Terminal to give the user greater control of the system. TAKING COMMAND The command line, or Terminal, is an extremely powerful interface. Everything you can do on the desktop can be done within the Terminal. Let’s start by seeing how it works. STEP 1 The Terminal can be accessed by either clicking on the Terminal icon on the Panel, located between the Firefox and files icons or launched by opening the Menu and selecting it from the left-hand quick launch…

Using the Terminal Install Apps via the Terminal — Part 2 Install Apps via the Terminal – Part 2 Most of the time you’ll get to install apps from the Terminal using the standard aptget command. However, sometimes an app demands a little more work. This means installing an app from its source code, which isn’t as scary as it first sounds. FROM THE SOURCE The commands you’ll need to become familiar with here are Configure, Make and Install. You’ll find a lot of apps use installing from source, so it’s certainly a skill worth investing time in. STEP 1 Source code files for Linux usually come in the form of .TAR.GZ or .TAR.BZ2. Both are compressed files holding all the core files needed to ‘make’ the app. Start off…

Using the Terminal Fun Things to do in the Terminal Fun Things to do in the Terminal Despite the seriousness of an operating system, the Linux community are certainly no strangers to a bit of fun. The developers over the years have created and inserted all manner of fun and odd elements into the Terminal. TERMINAL FUN You’ll be working exclusively in the Terminal for these next two sections, so start warming up your fingers. After all, all work and no play… as the saying goes. STEP 1 The first command we’re going to use is sl, it’s not installed by default so enter: sudo apt-get install sl. The command can be run with sl and when executed will display a Steam Locomotive travelling across the screen (hence ‘sl’). Entering…

Using the Terminal Did You Know… Linux and the Big Bang DID YOU KNOW… that Linux is at the heart of the science behind the Large Hadron Collider? Using a combination of Red Hat Linux and CentOS (an ultra-stable distro built from the Red Hat core) as the base distributions of choice, scientists, developers and engineers have created SL – Scientific Linux. Using SL as the base, the clever people at CERN have developed several different versions of their own custom Linux distro to help with all aspects of the LHC. Most notable is SLC, or Scientific Linux CERN, also known as CERN6. According to reports, there are over 36,000 systems running SL, and over 15,000 running SLC.…

Using the Terminal Creating Bash Scripts — Part 3 Creating Bash Scripts – Part 3 In the previous pages we looked at some very basic Bash scripting, which involved outputting text to the screen, getting a user’s input, storing it and outputting that to the screen; as well as including a system variable using the Date command. Now let’s combine what you’ve achieved so far and introduce Loops. IF, THEN, ELSE With most programming structures there will come a time where you need to loop through the commands you’ve entered to create better functionality, and ultimately a better program. STEP 1 Let’s look at the If, Then and Else statements now, which when executed correctly, compare a set of instructions and simply work out that IF something is present, THEN…

Using the Terminal Did You Know… Good enough for NASA DID YOU KNOW… that NASA’s state-of-theart supercomputing cluster, Pleiades, is powered by Linux? Pleiades consists of 160 racks (11,440 nodes), 245,536 CPU cores, a total memory count of 935TB, 184,320 NVIDIA CUDA cores, and over six miles of fibre optic cabling. At the heart of it lies a complex setup of SUSE Linux Enterprise Server, along with many custom development packages and other software unique to NASA’s projects. The projects NASA’s Advanced Supercomputing Division uses Pleiades for are: The Kepler Mission – searching for extra-solar Earth-like planets; CFD (Computational Fluid Dynamics) modelling to help create more efficient space launch systems; Dark Matter research and simulation; and visualisation of Earth’s ocean currents, building data for the ECCO (Estimating the Circulation and Climate…

Python on Linux How to Set Up Python in Linux How to Set Up Python in Linux While the Raspberry Pi’s operating system contains the latest, stable version of Python, other Linux distros don’t come with Python 3 preinstalled. If you’re not going down the Pi route, then here’s how to check and install Python for Linux. PYTHON PENGUIN Linux is such a versatile operating system that it’s often difficult to nail down just one way of doing something. Different distributions go about installing software in different ways, so we’re sticking with Linux Mint for this particular tutorial. STEP 1 First you need to ascertain which version of Python is currently installed in your Linux system. To begin with, drop into a Terminal session from your distro’s menu or hit…

Python on Linux Saving and Executing Your Code Saving and Executing Your Code While working in the IDLE Shell is perfectly fine for small code snippets, it’s not designed for entering longer program listings. In this section you’re going to be introduced to the IDLE Editor, where you will be working from now on. EDITING CODE You will eventually reach a point where you have to move on from inputting single lines of code into the Shell. Instead, the IDLE Editor will allow you to save and execute your Python code. STEP 1 First, open the Python IDLE Shell and when it’s up, click on File > New File. This will open a new window with Untitled as its name. This is the Python IDLE Editor and within it you…

Python on Linux Numbers and Expressions Numbers and Expressions We’ve seen some basic mathematical expressions with Python, simple addition and the like. Let’s expand on that now and see just how powerful Python is as a calculator. You can work within the IDLE Shell or in the Editor, whichever you like. IT’S ALL MATHS, MAN You can get some really impressive results with the mathematical powers of Python; as with most, if not all, programming languages, maths is the driving force behind the code. STEP 1 Open up the GUI version of Python 3, as mentioned you can use either the Shell or the Editor. For the time being, you’re going to use the Shell just to warm our maths muscle, which we believe is a small gland located at…

Python on Linux Python Modules Python Modules We’ve mentioned modules previously, (the Math module) but as modules are such a large part of getting the most from Python, it’s worth dedicating a little more time to them. In this instance we’re using the Windows version of Python 3. MASTERING MODULES Think of modules as an extension that’s imported into your Python code to enhance and extend its capabilities. There are countless modules available and as we’ve seen, you can even make your own. STEP 1 Although good, the built-in functions within Python are limited. The use of modules, however, allows us to make more sophisticated programs. As you are aware, modules are Python scripts that are imported, such as import math. STEP 2 Some modules, especially on the Raspberry Pi,…

C++ on Linux Your First C++ Program Your First C++ Program The Raspberry Pi makes for a great coding base on which to learn C++. You won’t need any complicated, third-party IDEs or to install any extra components. Everything you need to get started is already built into the Pi. HELLO, WORLD! It’s traditional in programming for the first code to be entered to output the words ‘Hello, World!’ to the screen. Interestingly, this dates back to 1968 using a language called BCPL. STEP 1 You can use the included Geany Programmer’s Editor to write, compile and execute your C++ code on the Raspberry Pi. You can find Geany as the first entry in the Programming section from the main Raspberry Pi menu. Click the Geany icon to open and…

C++ on Linux Did You Know… Virus! DID YOU KNOW… that one of the first programmed computer viruses that spread outside of a controlled system, i.e. into the wild, was called Elk Cloner and it was coded in 1982 by Rich Skrenta, a fifteen year old student. Elk Cloner was programmed to infect the Apple DOS 3.3 operating system, and attached to a game. When the game was played fifty times the virus would be activated and instead of displaying the game the virus would blank the screen and display a poem: Elk Cloner:The program with apersonality It will get on allyour disksIt will infiltrate yourchipsYes, it’s Cloner! It will stick to youlike glueIt will modify RAM tooSend in the Cloner!…

C++ on Linux Data Types Data Types Variables, as you’ve seen, store information that the programmer can then later call up, and manipulate if required. Variables are simply reserved memory locations that store the values the programmer assigns, depending on the data type used. THE VALUE OF DATA There are many different data types available for the programmer in C++, such as an integer, floating point, Boolean, character and so on. It’s widely accepted that there are seven basic data types, often called Primitive Built-in Types; however, you can create your own data types should the need ever arise within your code. These basic types can also be extended using the following modifiers: Long, Short, Signed and Unsigned. Basically this means the modifiers can expand the minimum and maximum range…

Index Say Hello to Linux Say Hello to Linux “How did you know so much about computers?” “I didn’t, it was the first one.”– Admiral Grace Hopper (pioneer programmer) when interviewed by David Letterman Why Linux? What is it? Where do I get it? Why are there so many different versions of it? Most beginners ask these, and many more, questions when starting out. It’s true that Linux is an incredibly versatile and powerful operating system but where do you start? Thankfully, you can find the answers in this section. There is so much you can do with Linux but you need to know where to start; we’re here to help you out. In this section you can learn what Linux is, what a distro is and what a desktop…

Say Hello to Linux Equipment You Will Need Equipment You Will Need The system requirements for successfully installing Linux Mint on to a PC are surprisingly low, so even a computer that’s several years old will happily run this distro. However, it’s worth checking you have everything in place before proceeding. MINTY INGREDIENTS Before we start working our way through this book, here’s what you need to install and run Linux Mint. You have several choices available, so take your time and see which works best for you. SYSTEM REQUIREMENTS The minimum system requirements for Linux Mint are as follows: CPU – 700MHz RAM/Memory – 512MB Hard Drive space – 9GB (20GB recommended) Display – 1024 x 768 resolution Obviously the better the system you have, the better the experience will…

Index Getting Started with Linux Getting Started with Linux “In real open source, you have the right to control your own destiny.”– Linus Torvalds (developer of the Linux kernel) It’s all fine and well talking about how good Linux is but how do you get it on your computer? Installing Linux is remarkably simple but there are several options available to you. This section looks into how you can download the Linux ISO, install it on a PC as your main operating system and even how to install a virtual environment. With a virtual environment you can run Linux while still using your main operating system, be that Windows or macOS. Intrigued? Read on and find out more.…

Getting Started with Linux Installing a Virtual Environment Installing a Virtual Environment A Virtual Environment is a simulated computer system. Using a Virtual Machine, you can mimic a standard PC and install an entire operating system to it without affecting the one installed on your computer. It’s a great way to test and use Linux, while still having Windows 10 as your main OS. GOING VIRTUAL Using a Virtual Machine (VM) takes resources from your computer: memory, hard drive space, processor usage and so on. Make sure you have enough of each before commencing. STEP 1 We’re using VirtualBox in this instance, as it’s one of the easiest virtual environments to get to grips with. Enter www.virtualbox.org and click on ‘Download VirtualBox’. This takes you to the main download page.…

Getting to Know Linux Introduction to the Cinnamon Menu Introduction to the Cinnamon Menu Now that you have Linux installed it’s time to have a good look around. First though, if you’re using Virtualbox you’ll have a notification regarding Software Rendering; here’s how to fix it. CINNAMON VIRTUALBOX FIX You’ve already looked at some list functions, using .insert, .remove, and .pop but there are also functions that can be applied to strings. STEP 1 Before we begin, we’re assuming you’re having this issue within Virtualbox. The Software Rendering message appears in the top right of the desktop. To fix this, click on Devices in the Virtualbox window, followed by Insert Guest Additions CD Image. STEP 2 The Guest Additions CD contains drivers for Virtualbox, including the virtual video hardware. When…

Getting to Know Linux Did You Know… Apollo 11 Credit: Apollo 11/NASA DID YOU KNOW… July 20th 1969 is remembered as a turning point in human history, when mankind first stepped on the moon. The software that helped the crew make that pivotal voyage didn’t even exist at the time and had to be developed from scratch. Using a new method of storing programs called Rope Memory, the engineers at MIT Instrumentation Laboratory populated the memory with a special version of assembly. Incredibly, that code is freely available to view on GitHub. Uploaded by a researcher in 2003, you can view the code by visiting www.github.com/chrislgarry/Apollo-11/. Look out for code snippets, such as Burn_Baby_Burn, in particular line 925 with the comment “Goodbye. Come again soon.” Have a look through, and…

Getting to Know Linux Becoming Anonymous Online Becoming Anonymous Online The digital age has led to many great advances in communications; however, it has also brought on a new age of spying and snooping. Most of us are no strangers to the frequent news stories of governments, secret organisations and underground hackers breaking our privacy but how can you combat this? ANONYMITY WITH MINT While it’s virtually impossible to become totally anonymous online, you can take measures to ensure our privacy is at its best. STEP 1 Starting with the basics, use HTTPS instead of the standard HTTP when browsing. This means that anything that’s transmitted over HTTPS is secure (hence the S part at the end) and encrypted. STEP 2 When you’re browsing, consider using the Incognito or Private…

Using the Terminal Update Mint via the Terminal Update Mint via the Terminal Up to now you’ve been using the shield icon to launch Mint Update Manager in order to update the system and upgrade the currently installed apps, tools and other elements. However, you can also accomplish a complete system update and upgrade from the Terminal. USING APT-GET To update and upgrade via the Terminal you use the APT (Advanced Packaging Tool) command. It’s a powerful command and combines different elements depending on its use. STEP 1 Start by opening a new Terminal or if you already have one opened clear its contents with the clear command. This starts you off with a clean slate on which to work. STEP 2 Enter: apt-get into the Terminal. This brings up…

Using the Terminal Creating a File Using the Terminal Creating a File Using the Terminal Using the Terminal, you’re able to create folders, files and even execute Linux Mint apps. In truth, if you didn’t have the GUI at hand, you could still accomplish the same from the Terminal. MORE TERMINAL WORK Creating content using the Terminal isn’t quite as strenuous as it may first appear. Yes, the Terminal can look a daunting place for the newcomer, but once mastered it’s really quite intuitive. STEP 1 Open up the Terminal, and make sure you’re in the Home folder. If not use the cd ~ command to return you to the Home folder from wherever you’re currently located. STEP 2 Let’s start by creating a new folder within Home, and call…

Using the Terminal More Fun Things to do in the Terminal More Fun Things to do in the Terminal If the previous list of fun, and quite bizarre, things to do in the Terminal has you wanting more, you’re in luck. We’ve put together another batch of some useful, and some not so useful, commands for you to try out. MORE FUN, YAY Since the Terminal session is already open, and your keyboard digits are nicely warmed up, here are another two pages of Terminal nonsense. STEP 1 Remember the old ZX Spectrum days of computing, when you could type in 10 print “Hello”, 20 goto 10 and Hello would list down the screen? Well, in Linux Mint you can do the same. Simply enter yes followed by some text,…

Using the Terminal Creating Bash Scripts — Part 1 Creating Bash Scripts – Part 1 Eventually, as you advance with Linux Mint, you’ll want to start creating your own automated tasks and programs. These are essentially scripts, Bash Shel scripts to be exact, and they work in the same way as a DOS Batch file does, or any other programming language. GET SCRIPTING A Bash script is simply a series of commands that Mint will run through to complete a certain task. They can be simple or remarkably complex, it all depends on the situation. STEP 1 You’ll be working within the Terminal and with a text editor throughout the coming pages. There are alternatives to the text editor, which we’ll look at in a moment but for the sake…

Using the Terminal Command Line Quick Reference Command Line Quick Reference When you start using Linux full time, you will quickly realise that the graphical interfaces of Ubuntu, Mint, etc. are great for many tasks but not great for all tasks. Understanding how to use the command line not only builds your understanding of Linux but also improves your knowledge of coding and programming in general. Our command line quick reference guide is designed to help you master Linux quicker. TOP 10 COMMANDS These may not be the most common commands used by everyone but they will certainly feature frequently for many users of Linux and the command line. cd The cd command is one of the commands you will use the most at the command line in Linux. It…

Index Python on Linux Python on Linux Python on Linux “Python is an experiment in how much freedom programmers need. Too much freedom and nobody can read another’s code; too little and expressiveness is endangered.”– Guido van Rossum (Developer of the Python programming language) Python is a fantastic programming language, combining ease of use with a generous helping of power to allow the user to create both minor utilities or performance-heavy computational tasks. However, there’s more to Python than simply being another programming language. It has a vibrant and lively community behind it that shares knowledge, code and project ideas, as well as bug fixes for future releases. We’ve used a Raspberry Pi for this section of the book, as it’s Linux based and one of the best coding platforms…

Python on Linux Starting Python for the First Time Starting Python for the First Time We’re going to be using the Raspberry Pi as our Python 3 hardware platform. The latest version of Raspbian comes preinstalled with Python 3, version 3.4.2 to be exact, so as long as you have a version 3 Shell, all our code will work. STARTING PYTHON We’re not going to go into the details of getting the Raspberry Pi up and running, there’s plenty of material already available on that subject. However, once you’re ready, fire up your Pi and get ready for coding. STEP 1 With the Raspbian desktop loaded, click on the Menu button followed by Programming > Python 3 (IDLE). This opens the Python 3 Shell. Windows and Mac users can find…

Python on Linux Executing Code from the Terminal Executing Code from the Terminal Although we’re working from the GUI IDLE throughout this book, it’s worth taking a look at Python’s command line handling. We already know there’s a command line version of Python but it’s also used to execute code. COMMAND THE CODE Using the code we created in the previous tutorial, the one we named hello.py, let’s see how you can run code that was made in the GUI at the command line level. STEP 1 Python, in Linux, comes with two possible ways of executing code via the command line. One of the ways is with Python 2, whilst the other uses the Python 3 libraries and so on. First though, drop into the command line or Terminal…

Python on Linux Creating Functions Creating Functions Now that you’ve mastered the use of variables and user input, the next step is to tackle functions. You’ve already used a few functions, such as the print command but Python enables you to define your own functions. FUNKY FUNCTIONS A function is a command that you enter into Python to do something. It’s a little piece of self-contained code that takes data, works on it and then returns the result. STEP 1 It’s not just data that a function works on. They can do all manner of useful things in Python, such as sort data, change items from one format to another and check the length or type of items. Basically, a function is a short word that’s followed by brackets. For…

Index C++ on Linux C++ on Linux “The most important single aspect of software development is to be clear about what you are trying to build.”– Bjarne Stroustrup (Developer and creator of C++) C++ is an excellent, high-level programming language that’s used in a multitude of technologies. Everything from your favourite mobile app, console and PC game to entire operating systems are developed with C++ at the core, together with a collection of software development kits and custom libraries. C++ is the driving force behind most of what you use on a daily basis, which makes it a complex and extraordinarily powerful language to get to grips with. It’s the code behind Linux itself, as well as most of the behind the scenes drivers, library files and control elements of…

C++ on Linux Strings Strings Strings are objects that represent and hold sequences of characters. For example, you could have a universal greeting in your code ‘Welcome’ and assign that as a string to be called up wherever you like in the program. STRING THEORY There are different ways in which you can create a string of characters, which historically are all carried over from the original C language and still supported by C++. STEP 1 To create a string, you use the char function. Open a new C++ file and begin with the usual header: STEP 2 It’s easy to confuse a string with an array. Here’s an array, which can be terminated with a null character: STEP 3 Build and run the code and ‘Welcome’ appears on the…

C++ on Linux User Interaction User Interaction There’s nothing quite as satisfying as creating a program that responds to you. This basic user interaction is one of the most taught aspects of any language and with it you’re able to do much more than simply greet the user by name. HELLO, DAVE You have already used cout, the standard output stream, throughout our code. Now you’re going to be using cin, the standard input stream, to prompt a user response. STEP 1 Anything that you want the user to input into the program needs to be stored somewhere in the system memory, so it can be retrieved and used. Therefore, any input must first be declared as a variable, so it’s ready to be used by the user. Start by…

Say Hello to Linux Why Linux? Why Linux? For many of its users, Linux means freedom. Freedom from the walled garden approach of other operating systems, freedom to change and use the OS as you please and freedom from any form of licensing or payment. There’s a lot more to Linux than you may think though. FREE AND OPEN Linux is a fantastic fit for those who want something different. The efficiency of the system, the availability of applications and stability are just a few good reasons. The first thing you need to know is that there is no such operating system called Linux. Linux is in fact the operating system kernel, the core component of an OS. When talking about Linux what we, and others, are referring to are…

Say Hello to Linux Desktop Environments Desktop Environments Linux Mint comes in several different versions, or flavours: Cinnamon, MATE and Xfce; there are 32-bit and 64-bit versions of these too. What does it all mean though and which version should you choose for your installation? WHICH MINT? A Desktop Environment is the graphical interface which you use to interact with the core Linux system. Just as the graphical desktop for Windows 10 is also called Fluent Design. Linux Mint offers the user a choice of versions of the distro: Cinnamon, MATE and Xfce. While that may sound a little confusing for the newcomer, essentially each of the versions available contains the same core Linux structure and kernel, the kernel is the core of the operating system, that handles all the instructions…

Getting Started with Linux Creating a Linux Installer on Windows Creating a Linux Installer on Windows You need to transfer the downloaded Linux ISO to either a DVD or a USB key before being able to install it onto a computer. This will be a live environment, which allows you to test the OS prior to installation, but first you need to create the bootable media. DVD BOOTABLE MEDIA We’re using a Windows 10 PC here to transfer the ISO to a DVD. If you’re using a version of Windows from 7 onward the process is extremely easy. STEP 1 First locate the ISO image of Linux you’ve already downloaded. You can usually find it in the Downloads folder in Windows 7, 8.1 and 10 computers, unless you specified a…

Getting Started with Linux Installing Linux in a Virtual Environment Installing Linux in a Virtual Environment With Oracle’s VirtualBox now up and running, the next task is to create the Virtual Machine (VM) environment into which you install Linux. This process won’t affect your currently installed operating system, which is why a VM is a great choice. CREATING THE VM There are plenty of options to choose from when creating a VM. For now though, let’s set up a VM adequate to run Mint Cinnamon and perform well. STEP 1 With VirtualBox open, click on the New icon in the top right of the app. This opens the new VM Wizard. STEP 2 In the box next to Name, type Linux Mint and VirtualBox should automatically choose Linux as the…

Getting to Know Linux Navigating the Cinnamon Desktop Navigating the Cinnamon Desktop Each desktop environment behaves differently to that of the next. Some DEs offer widgets that can be customised and placed on the desktop, others instead opt for a clean, sharp look to keep everything running as fast as possible. Let’s see what the Cinnamon desktop has to offer. A TOUCH OF SPICE The Cinnamon desktop environment is a great blend of style and performance. There’s lots to like about it, which is why it’s such a popular DE. STEP 1 Begin exploring the Cinnamon desktop by doubleclicking the Computer icon. This brings up Nemo, the file manager used in Cinnamon. The Computer icon opens up the root level file system, with access and views to the optical drive…

Getting to Know Linux Creating Users Creating Users When you first install Linux Mint it is configured for use with a single user. While sharing a user account with the entire family is fine, there may come a time when you need to create separate users with their own unique Home folders. NEW USERS Having different users means each user has access to his or hers own areas on the system. Documents, pictures, videos and so on are separate, as with multiple users on other operating systems. STEP 1 Click on the Linux Mint Menu and type ‘users’ to begin searching for the relevant console. From the search results, choose Users and Groups and enter your password. The Users and Groups console is quite basic looking, and thankfully easy to…

Index Using the Terminal Using the Terminal “Linux: the operating system with a CLUE… Command Line User Environment.”– Anonymous (Posted on comp. software.testing) The Linux command line, the Terminal, is an incredibly powerful environment. From it, you can bring the OS to its knees, or update it to something spectacular. You can hack into remote computers, look at an animated ASCII camp fire, install new apps and programs, watch Star Wars played out from a server in the Netherlands, and code intricate automated scripts. In this section you will explore the intricacies of the Terminal, and how it works with Linux. You will learn how to manipulate the Linux file system from the Terminal, and you will discover some odd, but fun things you can do in the Terminal. The…

Using the Terminal Install Apps via the Terminal — Part 1 Install Apps via the Terminal – Part 1 There are different ways to install apps and programs on Linux. You can opt for the graphical route, using a Software Manager, or you can use the Terminal. Often, the Terminal provides better control over the software being installed and sometimes, you have no choice in the matter. COMMAND LINE INSTALLS Installing an app with the Terminal may require some nifty keyboard work but you get a better sense of what’s being installed and where. STEP 1 Installing apps form the Terminal is often relatively simple. First though, you need to make sure that the system is up to date. To do this open up the Terminal and enter: sudo apt-get…

Using the Terminal Creating and Removing Directories Creating and Removing Directories As with creating files in the Terminal, you can also create and delete directories, or folders if you prefer. Directories form the structure of your file system, without logical directories the filing system would be in utter chaos. MANAGING FOLDERS Learning how to create and delete folders in the Terminal is an important Mint, and indeed Linux overall, skill to master. Here’s the basics for you to try out. STEP 1 With the Terminal open enter cd ~ to make sure you’re in your own Home directory. Now enter ls to view the current folders you have housed in the Home directory. You’ll notice that folders are labelled in Mint in cyan (light blue). Let’s start by creating a…

Using the Terminal Creating Bash Scripts — Part 2 Creating Bash Scripts – Part 2 Previously we looked at creating your first Bash script, Hello World, and adding a system variable. Now you can expand these and see what you can do when you start to play around with creating your own unique variables. VARIABLES Just as in every other programming language a Bash script can store and call certain variables from the system, either generic or user created. STEP 1 Let’s start by creating a new script called hello.sh; xed hello.sh. In it enter: #!/bin/bash, then, echo Hello $1. Save the file and exit Xed. Back in the Terminal make the script executable with: chmod +x hello.sh. STEP 2 As the script is now executable, run it with ./hello.sh.…

Using the Terminal Creating Bash Scripts — Part 5 Creating Bash Scripts – Part 5 The backup script we looked at previously can be further amended to incorporate choices, user-interaction with regards to where the backup file will be copied to and so on. Automating tasks is one of the main benefits of Bash scripting, a simple script can help you out in many ways. EASY AUTOMATION AND HANDY SCRIPTS Entering line after line of commands to retrieve system information, find a file or rename a batch of files? A script is a better answer. STEP 1 Let’s start by creating a script to help display the Mint system information; always a handy thing to have. Create a new script called sysinfo.sh and enter the following into Xed, or the…

Using the Terminal A-Z of Linux Commands A-Z of Linux Commands There are literally thousands of Linux commands, so while this is not a complete A-Z, it does contain many of the commands you will most likely need. You will probably find that you end up using a smaller set of commands over and over again but having an overall knowledge is still very useful. A adduser Add a new user arch Print machine architecture awk Find and replace text within file(s) B bc An arbitrary precision calculator language C cat Concatenate files and print on the standard output chdir Change working directory chgrp Change the group ownership of files chroot Change root directory cksum Print CRC checksum and byte counts cmp Compare two files comm Compare two sorted files…

Python on Linux Why Python? Why Python? There are many different programming languages available for the modern computer, and some still available for older 8 and 16-bit computers too. Some of these languages are designed for scientific work, others for mobile platforms and such. So why choose Python out of all the rest? PYTHON POWER Ever since the earliest home computers were available, enthusiasts, users and professionals have toiled away until the wee hours, slaving over an overheating heap of circuitry to create something akin to magic. These pioneers of programming carved their way into a new frontier, forging small routines that enabled the letter ‘A’ to scroll across the screen. It may not sound terribly exciting to a generation that’s used to ultra high-definition graphics and open world, multiplayer…

Python on Linux Did You Know… Space Invaders DID YOU KNOW… that when Space Invaders creator, Tomohiro Nishikado, was coding Space Invaders, he had to create his own hardware and development tools to write the game. Furthermore, he then discovered that as a result of the coding and the custom hardware, the fewer Invaders on-screen the faster the processor was able to render them. Thus, as you kill more Invaders, the faster they become. So rather than design the game to compensate for the speed increase, he decided to keep it as a challenging gameplay mechanism.…

Python on Linux Working with Variables Working with Variables We’ve seen some examples of variables in our Python code already but it’s always worth going through the way they operate and how Python creates and assigns certain values to a variable. VARIOUS VARIABLES You’ll be working with the Python 3 IDLE Shell in this tutorial. If you haven’t already, open Python 3 or close down the previous IDLE Shell to clear up any old code. STEP 1 In some programming languages you’re required to use a dollar sign to denote a string, which is a variable made up of multiple characters, such as a name of a person. In Python this isn’t necessary. For example, in the Shell enter: name=”David Hayward” (or use your own name, unless you’re also called…

C++ on Linux Why C++? Why C++? C++ is one of the most popular programming languages available today. Originally called C with Classes, the language was renamed C++ in 1983. It’s an extension of the original C language and is a general purpose object-oriented (OOP) environment. C EVERYTHING Due to how complex the language can be, and its power and performance, C++ is often used to develop games, programs, device drivers and even entire operating systems. Dating back to 1979, the start of the golden era of home computing, C++, or rather C with Classes, was the brainchild of Danish computer scientist Bjarne Stroustrup while working on his PhD thesis. Stroustrup’s plan was to further the original C language, which was widely used since the early seventies. C++ proved to…

C++ on Linux Compile and Execute Compile and Execute You’ve created your first C++ program and you now understand the basics behind the structure of one. Let’s get things moving and compile and execute, or run if you prefer, the program and see how it looks. GREETINGS FROM C++ Compiling and executing code from within Geany is remarkably simple and just a matter of clicking a couple of icons and seeing the result. Here’s how it’s done. STEP 1 Open Geany, if you haven’t already, and load up the previously saved Hello World code you created. Ensure that there are no visible errors, such as a missing semicolon at the end of the std::cout line. STEP 2 If your code is ready, look to the menu bar along the top…

C++ on Linux Variables Variables Variables differ slightly when using C++ as opposed to Python. In Python, you can simply state that ‘a’ equals 10 and a variable is assigned. However, in C++ a variable has to be declared with its type before it can be used. THE DECLARATION OF VARIABLES You can declare a C++ variable by using statements within the code. There are several distinct types of variable you can declare. Here’s how it works. STEP 1 Open up a new, blank C++ file and enter the usual code headers: STEP 2 Start simple by creating two variables, a and b, with one having a value of 10 and the other 5. You can use the data type int to declare these variables. Within the curly brackets enter:…

C++ on Linux C++ Maths C++ Maths Programming is mathematical in nature and as you might expect, there’s plenty of built-in scope for some quite intense maths. C++ has a lot to offer someone who’s implementing mathematical models into their code. It can be extremely complex or relatively simple. C++ = MC2 The basic mathematical symbols apply in C++ as they do in most other programming languages. However, by using the C++ Math Library, you can also calculate square roots, powers, trig and more. STEP 1 C++’s mathematical operations follow the same patterns as those taught in school, in that multiplication and division take precedence over addition and subtraction. You can alter that though. For now, create a new file and enter: STEP 2 While simple, it does get the…

C++ on Linux Did You Know… The Hobbit DID YOU KNOW… released in 1982 for various platforms, Melbourne House’s The Hobbit was a coding work of genius. Developed by Philip Mitchell and Dr. Veronika Megler, The Hobbit was uniquely coded using a parser called ‘Inglish’ which allowed the player to enter full sentences, such as “Take sword from Gandalf, and kill goblin with it.” Furthermore, each object in the game had a specific size, weight and solidity; so if you sat on a stool, and someone picked up the stool or threw it, then your character would be taken along with it. Also, in early versions of the game, the non-playing characters would often move around the map and capture and kill each other before the player had even reached that stage…