Linux FormatMay 2020的目錄

Jonni Bidwell I was preparing for second-year exams in a bleak coastal town in Fife. I believe graph theory, combinatorics, vector calculus and Fourier analysis were things I was supposed to know about. Three years later, I started using Linux as my daily OS. And look at where that got me. Nick Peers Two decades ago – a whole other life now – I was in my first editor’s role at this very publishing stable, on the short-lived Quick & Easy Windows. Luckily for me, I went on to better things – two years editing PC Answers, which is where I encountered Linux properly for the first time. Les Pounder 20 years ago I remember downloading Mandrake Linux on my 512KB cable internet. It took ages to download all the…

Firefox, the open source web browser, now enables encrypted DNS over HTTPS by default in the US, which Mozilla, the company behind Firefox, claims will address the current insecure DNS system used by many people to access the internet, and which leaves their data unencrypted. In a blog post explaining the feature (read it at http://bit.ly/LXF262DoH), Mozilla claims that its DNSover-HTTPS (DoH) protocol will protect its users by encrypting DNS traffic through its Firefox browser to resolvers via HTTPS, so Firefox users’ browsing behaviour can’t be intercepted by anyone spying on the network. Mozilla is working with Cloudflare and NextDNS, which have joined Mozilla’s Trusted Recursive Resolver programme (http://bit.ly/LXF262MozillaTRR) and will adhere to strict requirements on how they will handle user data. As Mozilla explains, “this includes placing strict limits…

“As I write this, it’s mid-March and COVID-19 is getting serious. Things are changing fast; anything I write will be out of date before I’ve finished writing it, let alone by the time you read it. So let’s look at how we IT professionals can best respond to some emergencies in general. Remote access to on-premises servers is easy to arrange. If you’ve nothing in place, the OpenVPN client runs on Linux, Windows, OSX, Android and iPhone. It’s relatively easy to set up, it’s flexible and it’s secure. Gobby is a real-time collaborative editor, allowing multiple participants to simultaneously see and edit a document. Zulip is a chat service, similar to Slack. It’s available as a paid service, or you can download and install it on your own server for…

SETI@home, a project started in May 1999 by researchers at UC Berkeley, that used the power of people’s PCs to help search for extraterrestrial life, is pausing, with the people behind the project saying they now have “all the data we need.” SETI@home used the computers of members of the public to help process transmissions around the world, and was initially shared as a screensaver, using people’s PCs while they were not in use. In the 20 years since the project began, it has accrued millions of years of computing time, and was even considered one of the most powerful supercomputers in the world. It has inspired other projects that use people’s PCs, such as Folding@home, a distributed computing project for disease research. The amount of data produced threatens to…

Q Lost password I successfully installed Linux Mint Cinnamon 19.3 on an old Dell laptop, previously on Windows 7. I promptly forgot the password. Determined as I was to try to recover/reset it I scoured all the info I could find, and although I seemed to be able to update the password, the new password is not recognised. Alexander Oyler A You need to use the passwd command to change passwords. However, in order to do that you will need to supply your old password first or run passwd as the root user. On Mint that means running it with sudo, which also requires your old password. This seems like a vicious circle, but all is not lost, there is a way around it – which, incidentally, is why…

When you start out with Linux, you may judge your distribution primarily by its desktop environment. So for this Roundup we’re going to take a closer look at what designers consider when they design a desktop. The “environment” is the window manager combined with the other elements you may have on your desktop. These are taskbars, icons and sometimes active elements on your desktop. Designers make desktop environments to appeal to all users. You may not be a generic user. While you read this, consider what your preferences are. The two dominating desktop environments are Gnome and KDE, and they have very different philosophies. For Gnome, it is to keep things available but not visible, while KDE chooses to stick with the menus at all times. The third big one…

When you use the standard desktops, Gnome and KDE, you will likely notice that you are using a lot of memory. In some cases, the CPU also increases quickly. As soon as you start several applications, the system will start swapping between them, which leads to slowdowns and sometimes hangs. If you haven’t noticed yet, try running htop in a separate window while you try out your choices. You should see a substantial difference with Awesome, i3 and, if you are elite, dwm. The difference in memory footprint is staggering when you start measuring. Gnome starts with somewhere in the region of 3GB at boot. This can be trimmed down by serious tweaking, but not very much. In comparison, the Awesome window manager weighs in at around 600MB. Getting the…

As we write this the latest systemd (version 245) is making its way into the repos of more adventurous distros. Of its many new features, systemd-homed stands out, as it (optionally) revolutionises home directories. Traditional static directories work fine for some people and some purposes, but these are problematic for things like network shares and require one type or another of ugly hack to successfully encrypt. Systemd-homed also takes care of user management, so that $HOMEs under its control are completely self-contained and portable. A compliant LUKS2 volume on a USB stick, or with a file of the form username.home in the /home directory, will be seamlessly mounted in the usual place upon production of the correct credentials. If the system is suspended it will be locked again. If you…

No matter what you do with your Linux servers you will almost certainly have SSH access to them. Indeed this might be the only access you have, so it would be wise to secure it. Naturally, you will already be using a strong password and will have already turned off SSH access for the root account (if you use a login for it). The latter is very important, but generally not necessary on Debian/ Ubuntu servers which use sudo for elevating privileges. Correcting it on other distros is just a matter of adding KEYS ADD EXTRA SECURITY “While the password you set here may be brute-forced or known to an attacker, they still need access to the keys.” to the /etc/ssh/sshd_config file and restarting the service. But we can do…

Pre-history – Linux Answers In late 1999 Future plc published a one-off magazine, this was borne off the back of the success of, the now closed, PC Answers and PC Plus [the flashbacks! – Ed]. Grab it from here https://bit.ly/LXA01. All we’ll say is that this was successful enough to launch a monthly magazine… May 2000 – Linux Format #1 Renaming the title in line with Future’s most successful print magazines: Amiga Format and PC Format, Linux Format was released with editor Nick Veitch of Amiga Format fame and writing talent from PC Plus mag. It came with a CD and was an instant hit. Here it is https://bit.ly/LXF001. November 2000 – LXF007 Corel Linux, the Debianbased distro, was on the CD. The OS may have failed but it was…

General Linux Lessons Practical Introduction – https://docs.ycrc.yale.edu/PIL Linux Journey – https://linuxjourney.com Lessons in Linux – www.lions-wing.net/lessons Command line Official Unbuntu – http://bit.ly/lxf262terminal Ryan’s tutorials – https://ryanstutorials.net/linuxtutorial Nano – http://bit.ly/lxf262nano Blogs for computer science teachers Mike Zamansky – https://cestlaz.github.io Alfred Thompson – http://blog.acthompson.net My blog – www.csforallteachers.org/blog/open-source-teaching Programming languages Microsoft TEALS program – https://tealsk12.gitbook.io/apcsa Computer Science Principles – http://bit.ly/lxf262cs EXLskills Java – https://github.com/exlskills/course-java-ap Cybersecurity High school guide – https://github.com/DerekBabb/CyberSecurity UoRI High School Cyber Project – http://bit.ly/lxf262cyber…

Distributed under LGPL 3.0, the utility is written in Python. This makes it cross-platform, meaning it can be installed on Windows or a Mac just as easily as on Linux distributions. You’ll find Glances in the software repository of most popular distributions, but if you want the latest version or you distribution doesn’t ship Glances, you can install it using pip with the pip install glances command. Apart from getting the latest version, another advantage of installing Glances using pip is that performing upgrades is as simple as running the pip install --upgrade glances . The tool makes use of many other Python modules to provide its myriad functionality. For instance, the Pygal library is used to chart graphs, and Bottle is used to provide a web interface so you…

One use for gLabels is to print out business cards, and these days people like to include their contact information in barcode (or more precisely QR code) form for quick and easy processing. Click the Create Barcode Object button and then click and drag to place your barcode on the page – by default, a basic barcode is created, but you can switch this via the Style tab’s Backend dropdown: choose QREncode for the more familiar QR code. Switch back to the Data tab – you can enter your text string (typically a web address for business cards) into the Literal box, or link to a field in a mail-merge document. If you wanted to use a more complex QR code – say one containing complete contact details in vCard…

The fun this issue is all about configuring a computer as a radio receiver. An introduction to GNU Radio concepts and its basic set up was provided in LXF261. This tutorial will expand on that knowledge to construct an FM radio receiver circuit with a flow graph. An antenna attached to a software-defined radio (SDR) dongle will capture a frequency-modulated (FM) broadcast radio-frequency (RF) signal. The signal will be digitally processed using GNU Radio software running on an Ubuntu 18.04 computer to produce an audio output. The reader can skip the set-up instructions that follow if they have completed the steps in LXF261 to install the GNU Radio application. Let’s refresh the Ubuntu install with: After installing the RTL-SDR dongle, use the command line to confirm that the hardware has…

Most mainstream distros, including Debian 10, now include the Wayland display server, which replaces the older Xorg (i.e. X11) server that has been used on Linux systems for many years. Wayland is claimed to be a simpler solution, but some very well-established programs, such as the Synaptic package manager, will not work with Wayland. Gnome, and KDE desktop managers will use Wayland, but the Mate desktop manager does not use Wayland, so Synaptic etc. will work. www.makeuseof.com/tag/using-linux-with-wayland gives a summary of some limitations of Wayland compared with Xorg. After installing Debian, Wayland can be disabled as follows: From a root terminal, enter: and then uncomment the line #WaylandEnable=false by removing the # character. Save the modified file and reboot the PC.…

The default Url is ‘myhost:8080/ guacamole’. Default login credentials are ‘guacadmin’ for both the user id and password. Part of an excellent Docker experience is the ability to quickly and easily download, start, stop, restart, and delete containers. You can also define, build, and delete custom Docker images quickly. Always remember to keep the docker rm and docker rmi commands handy at your fingertips as you cycle through images and containers. Docker Compose is a tool for defining and running multi-container Docker apps. Key command arguments are up, which starts the containers defined as services, and down, which will stop all services define. You can validate your YAML-based Docker app specifications using the command and syntax: docker-compose config --services…

Credit to Jason R Briggs for his partial solution for tkinter, and of course to game designers Howard Delman and Rich Moore for the first ever Lunar Lander on the Atari. Collision detection in video games is notoriously tricky to implement. Be sure to test-play your Lunar Lander to ensure both the win and lose scenarios are achievable for the player. It’s handy having a quick way to exit the program without having to play the game through in its entirety. It’s worth adding a ‘quit’ command for that reason. We’ve implemented some very basic collision detection. Like the last version of our game, if you come in too fast you’re going to crash, but if you land on the target with a speed of 5m/s or less you’ll win…

The source code for this project is located on the LXFDVD called tictactoe.py By using variables in place of hard coded values, the value only needs to be changed once, and not each time the value is used within the script. Two kinds of AI player have been implemented; one that uses the minimax algorithm and one that acts as a dumb AI player that just selects any available move at random. By default the minimax AI player is activated but to change to the dumb AI player, change the value of minimaxAI to False.…

Python is an interpreted, high-level, general-purpose programming language that was first released in 1991 by its creator, Guido van Rossum. Very similar in programming construct to how BASIC (Beginners All-purpose Sybollic Instruction Code) was used to teach logic, program control and flow. However, In this day and age, Python is much more powerful than BASIC ever was by providing libraries to include functionality for areas such as mathematics and science, computer communications, video games and media (Pygame), file data manipulation/conversion and so much more. Even though Python can be used as a learning tool to learn how to code, it can also be used in professional and commercial environments. In a lot of data-centred environments, Python can be used to retrieve data from files of different formats (Excel, Access, etc.)…

The best online resource for GDB debugging is its website (www.gnu. org/software/gdb or https:// sourceware. org/gdb), which includes an excellent documentation page with links to a manual (http://bit.ly/ lxf262manual) and a book. Which GDB? This article was written using Raspbian GNU/Linux 9 (stretch) on a RPi, with versions 6.3 of GCC and 7.12 of GDB. One of the best GDB cheat sheets goes by the name “GDB commands by function - simple guide”, compiled by shekkbuilder at http://bit.ly/ lxf262shekk.The best overall website on general debugging is http://bit.ly/ lxf262debug, which has an excellent subsection on GDB.…

GDB version 7 was a landmark release because it added support for new commands and functions coded in Python. One of the big areas this opened up was extending GDB’s printing capabilities. A great example of this is gdb-tools at https://github.com/vuvova/gdbtools, which can be downloaded and installed using Python’s pip (or pip3) package manager: gdb-tools includes DUEL.py, a Python version of Michael Golan’s DUEL language for printing C data structures. DUEL is imported into GDB by including the line python import duel at the start of your .gdbinit configuration file. DUEL supports an incredibly versatile expressions notation, which is used to print an array and a linked list of pointers in this article. For more details and examples, see the manual at https://github.com/vuvova/gdb-tools/blob/arpeggio/duel/help.md.…

We’re VERY aggressive around here at LXF Towers. Mexican art editor Effy runs a twice-weekly Fight Club in the sub-basement car park (this is an actual thing), while Jonni has been known to ring his bike’s bell at tardy headphone-using pedestrians on the Avon River cycle path. That’ll show ‘em. Meanwhile your erstwhile editor here is often found sticking passive-aggressive notes on monitors about people not refilling the coffee pot. Oh the humanity! You get the picture. As with most things involving open source and Linux, there’s a multitude of ways to solve a problem and a multitude of problems to solve. As we often do, we’re approaching protection with a broad brush stroke. This comes in three solid defences: firewalling your network, learning to audit and lock down your…

ProtonMail (https://protonmail.com), an encrypted email provider, could avoid censorship by routing connections to its servers via “third-party infrastructure and networks we do not control, some of which might belong to companies such as Google.” ProtonMail is an email service that puts heavy emphasis on protecting the privacy of its users by using client-side encryption, and it has often positioned itself as a secure and private alternative to Gmail – which means its reliance on Google’s infrastructure will certainly raise a few eyebrows. Because of its emphasis on encryption, ProtonMail has been subjected to censorship in countries such as Turkey and Russia, which has led to this rather surprising move. A new tool is being rolled out to ProtonMail users on desktop and mobile, which will avoid censorship by using alternative…

You can capture the output of a command by redirecting it to a file. What do you do if you want to save the output of several commands, or the commands you run are interactive, so you need to see what they ask to give the correct responses? The solution is a program called script. Run this from a terminal, with no arguments, and nothing will appear to happen apart from a message that script has started. Now run some other commands and everything appears to be just the same as normal. In fact, script has opened a subshell and is both displaying and capturing everything from whatever you type. Not only the output from the commands but your input too, even the shell prompts. Some programs behave differently when…

BradLUG BCB Radio, 11 Rawson Road, Bradford BD1 3SH. 7–9pm on the second Tuesday every month. http://bradlug.co.uk Cornwall Tech Jam Second Saturday of the month, alternating between Bodmin and Camborne. www.cornwalltechjam.uk Roanoke Linux Users Group Every third Thursday of the month at Roanoke South County Library. https://roalug.net Medway Makers Meet every 3-4 Weeks on a Sunday. Full details at www.eventbrite.com/o/medwaymakers-8800006845. Leeds Hackspace Open night every Tuesday 7pm-late. Open day second Saturday of the month, 11am-4pm. http://leedshackspace.org.uk rLab Reading Hackspace Unit C1, Weldale St, Reading. Open sessions Wednesday from 7pm. http://rlab.org.uk Huddersfield Raspberry Jam Meet every month at Huddersfield Library, typically the fourth Saturday of each month. Huddersfieldraspberryjam.co.uk PLUG: Provo Linux User Group Third Tuesday of every month at 7:00pm at the UVU Business Resource Center in Orem. https://plug.org Horsham Raspberry…

For this Roundup, we are investigating the reasons for choosing a desktop environment. The amount of choice out there could see you spending hours of effort (hopefully with a wide smile on your face) as you test each one. First, you need to know why designers made the choices they made so you can see if you agree. To be certain about your choice, you want to know about the learning curve and if you can aesthetically fit your applications in to the particular environment. You need to know which applications depend on desktop features to operate correctly and where you need to take extra steps to make it work. After you’ve overcome the learning curve, you can continue measuring how it feels to use each environment. The ones that…

If you have a bit of programming experience, you should seriously consider the dynamic window manager (dwm) that is part of the (see LXF254) Suckless tools. They make these tools with one goal in mind – minimal footprint. The tools are available as binaries from your distribution. However, that defeats the purpose of the Suckless tools – namely, that you add the features you want and only those, then compile your binary. Once you have the binary there are no more settings, except you can use X settings files for some settings. You add the settings and features by patching your source code, all written in C. It may sound daunting to a non-programmer, but the only small problem is to patch. If you pick too many patches in the…

When UEFI was introduced to address the diverse and varied shortcomings of using BIOS to initialise hardware, it was met in some circles with a chilly reception. Most of this centred around UEFI’s Secure Boot extension, which at the time made it hard for consumers to replace Windows 8 (which at the time was being shipped on new machines), or even boot a Linux distro. Much of that criticism was unjust, Secure Boot is meant to enable administrators to limit which bootloaders can run and which kernels they can boot. Most x86 hardware ships with Microsoft’s Secure Boot public key pre-baked in, which permits booting only Microsoft-signed bootloaders. Some Linux distros provide a boot manager signed by Microsoft – there are two approaches here, Fedora’s Shim (also used by Ubuntu…

If you want to use YubiKeys in your own applications, and issue physical keys directly to trusted users, then check out the developers’ guide at https://developers.yubico.com/OTP. The YubiCloud service provides free authentication for YubiKeys (which come set-up for OTP out of the box), but they also provide open source software so that you can host your own auth server, in the spirit of decentralisation. YubiKeys ship with their own unique AES key, which enables them to be verified by YubiCloud (which holds a copy of it). Locally, the symmetric key is locked away in the hardware, and while it’s invisible to software it can still be changed. This is fine if you’re doing your own authentication, but even though you can register the new key with YubiCloud, the same level…

Looking for a way to print labels or business cards using special paper? You can, of course, make use of LibreOffice’s built-in tools, but a simpler, more elegant method can be found with gLabels. This self-contained tool is designed to simplify the task of creating and printing all kinds of labels, cards, and photo collages, including CD/DVD covers. Whereas LibreOffice’s template provides you with a sheet of preformatted labels, each of which has to be customised individually, gLabels provides you with the tools to create a single design for all your labels, with the option of inserting data from a mail merge if you’re looking to print-out personalised labels such as addresses, as opposed to static elements like business cards. Once your basic template is chosen, you’re free to design…

gLabels is designed to be used from the desktop – you can open one or more labels from the terminal using the glabels file1.glabels file2. glabels command, but that’s it. If you’d like to generate labels from the Bash shell, you’ll need a dedicated app: LabelNation (www.red-bean.com/labelnation). The simplest way to install it is as a snap: sudo snap install labelnation, then run labelnation to read the comprehensive help file explaining exactly what it is capable of doing and how it works. LabelNation takes the input of a plain text file, which can be a simple text file containing a list of identically formatted names and addresses or a CSV file. It then formats this according to your choice of label template (a few dozen standard sizes are supported –…

A RTL-SDR Blog V3 R820T2 RTL2832U 1PPM TCXO SMA software-defined radio with dipole antenna kit, from RTL-SDR.com, was used for this tutorial. The kit contains both the RTL-SDR dongle and an adjustable antenna. This is not an endorsement of the product. The information is provided to enable the reader to complete the exercise in this tutorial. Other kits and/or dongles and antennas sold separately may work in this exercise. Not all RTL-SDR dongles are the same. Price and design technology are extensive. They can range in price from as little as $10 to over a $1,000 (all prices in Canadian dollars). The dongle used in the tutorial was $40. Some dongles, like the device for this tutorial, have technology that make them more stable. The dongle contain frequency oscillators and…

If this is your first attempt at installing Linux, then try installing onto an old/spare PC to see how it goes and to figure out just what you want Linux to do. If you don’t have a spare PC, then temporarily swap your existing hard drive for a small/spare/ cheap hard drive. Use Synaptic to discover new apps. e.g., search using “astronomy” to find ‘stellarium’ and ‘kstars’ planetarium applications, or “radio” to find ‘rtl-sdr’, which is a software-defined radio (SDR) receiver software for certain low-cost DVB-T/ DAB(+) USB dongles based on the Realtek RTL2832U chip.…

Start a terminal screen window from your desktop manager. This will show the username and computer name, and will end with an $ character. Enter Nano and use this text editor to practise reading, writing, and modifying files. Now exit Nano via Ctrl+X. Enter su, followed by the root password. The cursor will then terminate with a # character. Be very careful! You will now have root access and will be able to modify many of the critical system files. To exit the root terminal enter exit. The cursor will then again terminate with $. Another exit will terminate the terminal screen. To get root privilege on a live-derived system, enter sudo followed by the command needed, and then the user password. Before modifying a file, copy it to a…

You can leverage the backend SQL table schema and insert server-connection details directly, providing an alternative to the web admin interface. In this scenario, database tables guacamole_collection and guacamole_connection_parameter are key as they persist connect name, server target, and associated metadata. To insert parent entry, begin with this SQL statement that specifies name and protocol: INSERT INTO guacamole_connection (connection_name, protocol) VALUES (‘cld-linux-server’, ‘vnc’); Insert the connection parameters, including hostname and port. INSERT INTO guacamole_connection_parameter VALUES (1, ‘hostname’, ‘localhost’); INSERT INTO guacamole_connection_parameter VALUES (1, ‘port’, ‘5901’); Inserting into these tables and leveraging the Connect storage engine that is available for MariaDB, you can bulk-import a server list from an external CSV file containing key server data. The Connect storage engine is available by installing mariadb-plugin-connect. After installation, map a CVS file…

Have a go at turning our game from one player to two. All three of our Lunar Lander games have been programmed as single-player experiences. Since our third implementation uses object-oriented programming it shouldn’t be too difficult to add a second player to the mix. We’d need to initialise an additional lander object and potentially a second platform, depending on if you wanted this to be a straight race or more of a first-past-the-post competition to a single landing pad. We’d need to use a second set of keys (usually WASD) to control the engine and thrusters, but other than that the rest of the functions in our code should suffice. Try renaming the main Lander function to playerOne and introduce a similar function called playerTwo. It might also be…

Object-orientated programming has been used to quite an extent in this project. For those readers who are not yet familiar with object-orientated programming, it is an approach of writing software in terms of classes and objects. A class can be seen as a template of an object. A class can contain both variables and functions (usually referred to as methods) that define behaviour and operation. For example, in tictactoe.py, there is a class implemented called Player. This class contains methods for what actions are player is able to perform during the game. In the case of the Player class implemented, two methods exist: performMove and getAvailableMoves. You may notice that there is a method called __ init__, which is used to initialise variables with values if needed. This is also…

GDB has an undeserving reputation as being complicated to use, mostly because of its old-style command-line interface. In fact, there are numerous GUI frontends for the tool, including DDD (www.gnu.org/software/ddd), CGDB (https://github.com/cgdb/cgdb), GDB dashboard (https://github.com/cyrus-and/gdb-dashboard), and gdbgui (www.gdbgui.com). However, its text-based interface (TUI) is built in, simple to use and understand, especially when debugging C code. Faulty code should be compiled by GCC with the necessary flags, and loaded into GDB: -ggdb3 makes GCC save the maximum amount of debugging information, while -O0 switches off any optimisations that might affect that data. -std=c99 indicates that the code follows the C99 standard. GDB’s -tui flag switches on the TUI, and -q disables the printing of GDB’s licensing preamble. Debugging to the max The code max.c (all the code can be found…

GCC can find a very large number of errors, and possible errors, making it less necessary to resort to GDB. At the very least you should call GCC with the -Wall, -Wextra, and -pedantic flags. The first two switch on a slew of warning flags, while -pedantic strictly applies the ISO C standard for C99, as specified by -std=C99. For example: In fact, there are so many potentially useful GCC flags that it’s convenient to place them in a separate text file, warns.txt, and reference that on the command line: For example, the warns.txt included with this article also holds flags to colorise and simplify GCC’s error reporting. It’s also a good idea to download the cppcheck static analyser (http://cppcheck.sourceforge.net), and let it peruse your C file. For example: Suitable…

“I’ve gotten to meet some wonderful and highly regarded people through my employ in the strange world of dead tree tech publishing. But I must say this month’s assembly of LXF editors past and present was really quite special. There are those who say making magazines was more fun back in the day, but they probably know very little of my antics. Naturally, magazines at Future Towers are a lot more uniformly treated nowadays. LXF, when I joined, still described itself as “an isolated silo of maverick publishing”. Now we have to make our covers please not only our art editor, who strives for perfection in everything, but also management, who get scared of Linux argot. Somehow we make it work, exactly how those Jupiters of LXF-past did, when challenged…

“Some good things have happened recently in the land of Monado, the OpenXR runtime for Linux. Ever since announcing it at GDC 2019, we have been working at improving the full open source XR stack to a usable state, and recently we have finally been able to tag version 0.1. While this is only a first tag, it is a very significant milestone nonetheless. Along with this tag, there have been a number of noteworthy additions to the project in recent months. Notably, the Project North Star driver, made by Nova, has been merged. This is for an open source optical see-through AR headset that supports positional tracking using the Intel RealSense T265 tracker, which lives in a separate driver and can be reused. We have also made good progress…

We’d love to try and answer any questions you send to lxf.answers@futurenet.com, no matter what the level. We’ve all been stuck before, so don’t be shy. However, we’re only human (although many suspect Jonni is a robot), so it’s important that you include as much information as you can. If something works on one distro but not another, then tell us. If you get an error message, please tell us the exact message and precisely what you did to invoke it. If you have, or suspect, a hardware problem, let us know about the hardware. Consider installing hardinfo or lshw. These programs list the hardware on your machine, so send us their output. If you’re unwilling, or unable, to install these, run the following commands in a root terminal and…

Documentation is absolutely necessary, but many maintainers and coders hate writing it. For the major names, you have great documentation thanks to big organisations. Canonical has the Gnome version of Ubuntu, so you will find a lot on their website. Gnome also has a great site that is split between users, administrators and developers. The KDE website also has everything covered, with a different design but great content. To find any help about Cinnamon, start from the Linux Mint webpage – there are numerous PDF documents available. Development happens on GitHub. You can find most information on the spices page. if you want to make extensions, find links at https://github.com/linuxmint/Cinnamon/wiki. Just like in Gnome, extensions are written in JavaScript. At first glance, the Awesome’s webpage has a link to the…

WHAT’S TO COME… “We will look at everything from next-gen logins with hardware tokens to basics like SSH keys.” When you install Linux on your desktop, then as long as you install an up-to-date distro the chances are you’re reasonably secure. The same is true for servers, as long as you choose a strong password (or disable password access altogether and use SSH keys instead). There’s a faction of the Linux-using populous that still likes to bang the “Linux is more secure than Windows” drum, but this isn’t really true anymore. Both Linux and Windows have multiple layers of security coded by very smart people. Both Linux and Windows rapidly patch emergent security issues. And neither Linux nor Windows can do a whole lot about flaws in whatever software people…

IPFire has everything you need and more to run an advanced firewall solution. But its functionality can be extended far beyond what’s in the box. For one thing, it’s its own distro with its own package manager (Pakfire), which can be used directly or behind the scenes to install extra functionality. We’ll talk briefly later about the pros and cons of VPNs, but if you think you need one, you can set it up via OpenVPN with just a few clicks. Two configurations are offered – the appropriately apocalyptic-sounding Roadwarrior, and the more descriptive Net-to-Net. The former may equally have been called client-to-net, and is just what’s required for you, a Roadwarrior far outside safe network connectivity, to encrypt your communications back to your trusted server. Tor, often spoken of…

For any teacher, there will always be challenges when mastering a new curriculum. However, the biggest roadblock experienced was working in a computer lab that was governed by district information technology policies, which created some serious problems. The speedbumps began with a unit on programming robots. The district only supported Windows computers in the classroom, and security settings prevented the loading of software or accessing USB devices. In the true spirit of IT professionals, we discovered multiple ways that Linux could get around imposed barriers and enabled students to gain an authentic appreciation of the things Linux could accomplish. Over time, the classroom evolved and the students were able to use a dedicated Linux network in parallel with their Windows and Mac workstations. In the ECS classroom, students learn the…

Getting students to start the Linux operating system from the USB drive is only a first step. Writing program code or scripts requires the use of a text editor. A solid choice for a simple yet capable editor is Nano. While more complex programs are available, Nano is installed by default on virtually every distribution. Many computer science teachers will show students how to navigate a more complete IDE such as Eclipse, but for beginners Nano has proven to be totally adequate for writing code in Python and C, creating Bash scripts and editing system configuration files. In the classroom, students write their first text-based programs using Python. It is important to show them how to name files correctly and navigate the directories on their storage devices. Invariably students seem…

Debian Live distros provide an easy way of trying out Debian. www.debian.org/CD/live suggests users download BitTorrent files, but users might prefer to download normal ISO files, which include “non-free” packages. Find these at: http://bit.ly/LXF262debian. Choose amd64/ or i386/ then iso-hybrid/ and then select an ISO file. The selection of desktops is Cinnamon, Gnome, KDE, LXDE, LXQt, Mate, or Xfce. These DVD-sized ISO files can be transferred to a DVD or to a memory stick as described for the netinst files. Note the information in our boxout “Wayland, Xorg, compatibility”. On booting from the DVD/memory stick, a start-up menu provides for loading a live version of Debian into RAM (as is done for Ubuntu Linux and Linux Mint). This will show how the operating system looks and works, but it will…

Guacamole offers ready-to-run installation packages that are available for Linux distros such as CentOS or Debian. However, the thrust of this article is to illustrate running Guacamole in a Docker container context. Fire up an environment where you have access to the Docker command line and where you feel comfortable to pull and run Docker images. It’s recommended that you evaluate Guacamole in a sandbox that has Docker tooling installed. The Docker command line should have access to the default registry maintained at hub.docker.com. To verify which registry your Docker tooling is pointing to, type this command: Scan the output of this command-line tool for Registry and confirm that this field includes index.docker.io (or possibly a mirror of this registry). The next step is to search for the official Guacamole…

In this new Python series we’re going to be developing classic video games using contemporary techniques. This issue we’re kicking things off with the legendary Lunar Lander. Lunar Lander games are a genre originating from the original Atari back in 1979, and are one of the oldest video game genres. The player controls a lander spacecraft and attempts to land the spacecraft by controlling the thrusters, while monitoring forces and fuel levels, with the game round ending in either a crash or a successful landing, most commonly the former. Points can be given for time and precision of landing. The game world is black and white with vector graphics, displaying the environment and lander module in a 2D environment. We need to set up measurements for our lander’s fuel levels,…