Indholdsfortegnelse for October 2019 i Linux Format

“As well as expecting you to manage multiple servers, most businesses would like (or require) an audit trail of changes made. A Configuration Management System – CMS, not to be confused with Content Management System – provides a central point to manage multiple systems. If you keep the CMS configuration in a repository such as Git, you have the start of an audit trail. Some of the more popular CMSs include Ansible, Salt and Puppet, but the principles of each are similar. You define, on the CMS server, the configuration you want for your servers, and the CMS makes that happen. If you have multiple servers fulfilling the same role, such as web servers, you need only define that role once. Make a change to that role, and all the…

A nasty backdoor has been found in Unix administration tool Webmin, and researchers believe it was deliberately planted around a year before its discovery. The backdoor allowed anyone who knew about it to execute root commands, potentially allowing attackers to take control over an endpoint. According to Jamie Cameron, the author of Webmin, “the Webmin source code had been maliciously modified to add a non-obvious vulnerability,” with versions 1.890, 1.900 and 1.920 all having the backdoor code, which was added to the password_change.cgi script. The backdoor was discovered at the DEF CON 2019 hacking conference (www.defcon.org),when a researcher released zero-day research that showed how a bug could make use of the vulnerability. To mitigate against the vulnerability, Webmin has updated the build process to only use checked-in code from GitHub,…

“Open source has truly changed the world, even as many of us who got into it early on have watched with our own eyes. Today, similar trends are happening in the world of hardware, as we saw with first the Maker movement and latterly the Open Source Hardware community efforts to build fully open-source computer architectures like RISC-V. One of the great things about Open Source Hardware is the availability of powerful tools for learning. These include low-cost devices designed for software radio that can be used by enthusiasts such as ourselves to understand how systems really work. In this issue’s update, I mention a recent Bluetooth vulnerability, KNOB, which impacts the process of key exchange between two devices. This reminded me of some earlier experimentation I had done with…

Q Unauthorised address I have installed CentOS 7 in VirtualBox. I tried to send an mail using the mail command like this: But I get this error message: The IP you’re using to send email is not authorized...... I tried clearing the IP mentioned in the above error logs from SPAMHAUS and no luck. What could be reason I am not able to send email from my Linux server to any external email account? What is needed to get this resolved? Julie Pirouet A The mail command needs an SMTP server in order to send mail. If you haven’t specified one on the command line, I will assume you are using Postfix running locally, as that is the default configuration of CentOS. So mail (the command) sends your email to…

The Radeon RX 5700 is the second of AMD’s new Navi 10 graphics cards, sporting the new and improved RDNA architecture, and playing second fiddle to the RX 5700 XT’s leading role. The RX 5700 uses the same Navi 10 GPU as the other 5700 models, but AMD disables four Compute Units and 256 cores, as well as dropping the boost clock by 180MHz. That’s typical for the second-tier product for any GPU, and the reason comes down to chip yields. RX 5700 cards likely won’t hit the same clock speeds as the 5700 XT, no matter how hard you try to overclock. Overall, pretty much regardless of what setting you choose, the Radeon RX 5700 comes out ahead of the slightly more expensive RTX 2060. It’s five per cent…

Diminutive little machines that have served us faithfully for years now line our attics – and all because they can’t cater to the needs of resource-guzzling releases from the mainstream distributions. But you can’t really blame the distributions. The projects have to appeal to a large number of users, which forces them to make unprecedented demands on the hardware. Many also lack the resources and manpower to support hardware that’s not in vogue anymore. That would explain why many popular projects – everything from beginner distros such as Solus and elementaryOS to the privacy-centric Tails Linux – don’t support the 32-bit platform. Even mainstream projects like Arch and Ubuntu no longer offer installation ISOs for 32-bit machines. Ubuntu even considered dropping support for the 32-bit platform altogether, but had to…

Keeping away from mainstream desktop environments and apps means these lightweight distros aren’t the most straightforward and intuitive to operate. You’ll need some good avenues of documentation and support if you plan to use them on a regular basis. Once again, the candidates are all fairly equally matched in this aspect. BionicPup has ample documentation. The distro bundles help documentation on several topics, such as working with Microsoft Office files, how to add codecs, installing software and more. Help pages also contain links to the documentation pages for most applications, and there’s a dedicated board on Puppy Linux’s forum. Q4OS too hosts ample information to assist new users with installations. Besides the user-centric information, there’s also several pieces of administration and developer-orientated documentation. If you get stuck you can take…

LXF: For the benefit of… well, me, really, tell us a bit about the history of GStreamer. OC: GStreamer started in 1999 when we were very young. On Windows [at that time] there was something called DirectShow, and Apple had QuickTime. They’re basically frameworks where you have elements, you link them together linearly, in a pipeline, and they do the media processing for you. GStreamer is exactly that idea copied into an open source framework. The first five or six years saw a lot of churn – things went from version 0.1 to version 0.2 to 0.4, 0.6, 0.8, 0.10 and each version was a complete redesign of the framework. But then at 0.10 they must’ve got something right because it really took off. That version we kept for 10…

In addition to Fuchsia being a great research operating system – ideally suited as a playground for up and coming computer scientists – Google is probably using some kind of subsistence growth strategy for it, in a fashion similar to what Samsung did with its LED business – which grew out of the camera LEDs used on phones such as the Galaxy S2. Real-time/embedded operating systems were traditionally insanely expensive. Cost savings, however, are likely to be but one factor; Google is rich, and could easily afford a total buy-out of the largest of RTOS houses. All the money in the world can not, however, create a version of Linux which is free of the GPL; with Fuchsia, Google has less risk of annoying legal problems. Finally, the microkernel architecture…

One of the key aspects of using a Raspberry Pi involves copying data to it. This could be anything, depending on your use; perhaps you have a Bluetooth audio streamer project on the go, or a digital picture frame. You may need to send over a directory of MP3 files to play, or PNG images to view. Dumping the files to a USB stick on your PC then dragging them from the flash storage on your Pi is one option. It’s straightforward, but lacks finesse, and adds too much physical interaction. Instead, it’s smarter to use a network option, taking advantage of the local network to beam the data wirelessly or over Ethernet from your PC to your Pi. You might even set up a network share and make your…

If you’re more comfortable at the command line or want a swifter way to manage your apps, here’s what you need to know. First, the key command you’ll need to master is apt-get – this is used to update repos, plus install and upgrade software. Get in the habit of updating repos before installing any new software: This ensures the package lists are fully updated with both the latest versions of available packages (along with their dependencies) as well as any new programs that have appeared in the repos. Now you’re free to install your program – in the examples that follow, substitute audacity with the name of the package or program: If you can’t identify the program’s package, try the following: This uses your program name in a keyword…

We discuss root and non-root apps as ways to utilise Linux tools on your Android device. However, there’s an even simpler way: remote into your favourite Linux box. You have two options here: Connect with terminal programs. In addition to the SSH client you can install within Termux, Android has some great standalone apps. Connect Bot (http://bit.ly/LXF255bot) and its fork VX ConnectBot (http://bit.ly/LXF255bot2) are good examples, as is the highly-rated JuiceSSH (http://bit.ly/LXF255juice). Connect to your Linux rig’s graphical desktop, if it has one. There are plenty of clients for the VNC and RDP protocols, or get an app that supports both, such as Jump Desktop (http://bit.ly/ LXF255jump). NoMachine (www.nomachine.com) also offers a product that works well and is free for personal use. Of course, this approach has three disadvantages. Firstly,…

Backups are essential for administering a fully functioning webserver. Be sure to back up any directories from which Apache serves content, and any and all configuration files to which you may later need to revert. You might have heard about this neat little trick you can do to your server to make it work a lot faster – but it’s important to actually make it work first! If you’re going to be the sysadmin of your own server, you’ll want to get really comfortable with a text editor for those configuration files and all the shortcuts for it.…

So your computer is (hopefully) connected to the internet either through a Wi-Fi connection or an Ethernet cable. When you go online your http header requests have to go to the correct places and IP addresses play a significant role in making sure that happens. To allow for these connections to happen the networking software is programmed to follow a list of rules and standards and of course protocols. One such protocol, the IP (Internet Protocol); is responsible for addressing and delivering the requests precisely. It also uses an electronic return address to all activities. The address it uses to send the data packets back is the IP address assigned to your network. Think of it like a return to sender address. IP addresses cover 2 things in a computer…

Guacamole is a open-source software project consisting of a client and server component that work together to enable remote connectivity to server environments from a web browser. In fact, this open-source project goes back as far as 2010, having spent several years being maintained on SourceForge, with varying periods of development and interest from the Linux community. The project reached a milestone 1.0 release at the beginning of 2019. In its current state, Guacamole is a nicely matured open source project with high-quality code and runtime components that have a straightforward configuration model, yet it also offers a more advanced configuration and enterprise integration to bolster security and user management, for example. Guacamole offers ready to run installation packages for distros such as CentOS or Debian. However, the thrust of…

The best way to follow along with this guide is to get the files for this tutorial from the DVD or from https:// github.com/jschwartzman/ asm-tutorial. The stack is critical for making programs run. Linux allocates a stack for every program that it executes. The stack grows downward. Each time you push a value onto the stack, the stack pointer (RSP) is decremented by eight bytes. Each time you pop a value off of the stack, RSP is incremented by eight bytes. The top of the stack that RSP points to is really the lower end of the stack. In order to be able to step the debugger into C library functions, you’re going to need to use C library code which is debug-enabled. We needed to install glibc-debuginfo and glibcdebugsource…

When using Turtle Graphics, to check if your pen (or paintbrush) is up or down at any given time, use print teddy.isdown() , where teddy is the name of your turtle. You can change the speed of your turtle on a scale of 1 to 10, 1 being a turtle, 10 being a hare. Use teddy. speed(10) with teddy being your turtle’s assigned name. Try changing the makeTree function to spawn other types of foliage, too. This function could be used to populate large parts of an empty or flat Minecraft world with one simple click.…

Just in case you don’t have last issue to hand, here are some handy tips for downloading and installing Minecraft and the relevant mods to get this tutorial working. Ensure you have the appropriate version of Minecraft for your distro of choice. Mojang offers pre-packaged solutions for Debian/Ubuntu and Arch (DEB and AUR respectively), and a generic Java version for everyone else, at: www.minecraft.net/en-us/download/alternative. Next you’ll want to make sure you’ve got Python installed. sudo apt-get install python should suffice for any Debian-based distro (after a sudo apt-get update , of course). Before installing McPiFoMo it’s always best to backup your Minecraft folder first; in fact that’s a good rule of thumb to follow before making any changes. It can be found hidden in your /home as .minecraft.Ctrl+H can be…

USING THE LXFDVD Using Linux for the first time can be very confusing. It’ll be unlike anything that you’ve likely operated before, especially if you’re used to Microsoft Windows or Apple macOS. Generally our DVDs are designed to be run directly, which is to say that when you first power on your PC (or Mac) it should ‘boot’ from the DVD – so before Windows or macOS even starts to load – with Linux running directly from the DVD. This trick is known as a Live Disc. It enables you to try out the various versions of Linux without having to install or change anything on your PC. Just remove the DVD, restart your PC and it’ll be exactly as you left it. While many systems will boot from a…

There’s no better, friendlier introduction to using Linux than Linux Mint. If you’re picking up this magazine for the first time, hello and welcome to Linux: the open, smart, friendly way to use a modern PC. Best of all, it’s all been freed for you to use – liberated, you could say – so you’re free to install it, use it and modify it however you would like to. Linux and the accompanying library of open source tools means you’re no longer locked to a single OS vendor, a single desktop or a single app store. Coded and maintained by an army of developers across the globe, this sometimes means things might not be as slick as under macOS or Microsoft Windows, but we think that’s more a strength of…

There’s been a spate of good news concerning Godot, the open-source game engine that allows anyone to create their own games without having to pay for expensive tools or licensing. First of all, a new progress report on the state of Vulkan support (https://godotengine.org/article/ vulkanprogress-report-2) in Godot explains in detail how things are improving. For example, 2D lighting is now done in a single pass, for better performance. Custom shader support for 2D materials with the new Vulkan renderer has also been implemented, and the results so far are impressive. Not only do the graphics look great, but performance has again been improved – there’s now no sign of pausing or stalling in a game when compiling a shader (which happened in previous versions of Godot) thanks to shaders now…

Pine64 (www.pine64.org), the company behind the Pinebook Pro laptop and PinePhone smartphone, has announced that it will be giving the profits it makes on the PinePhone back to the Linux community at large. As the announcement states (http://bit.ly/ LXF255Pine644 ), “We have now made the decision to relay all revenue from PinePhone sales to the development community and third-party Linux-on-phone projects.” The move is not only aimed at helping other Linux-on-phone projects succeed, but to encourage developers to work on PinePhone –something the team is refreshingly transparent about. The plan is to give the $10 profit of each PinePhone sold back to the community. The Pinebook and Pinebook Pro do not make a profit (according to the team), which is why the PinePhone has been chosen. It means anyone who…

Linux turned 28 years old in August. As it happens, the anniversary aligned perfectly with the announcement of 5.3-rc6, so Linus reprised his original announcement with a few contemporary changes: “Hello everybody out there using Linux – I’m doing a (free) operating system (more than just a hobby) for 486 AT clones and lot of other hardware. This has been brewing for the last 28 years, and is still not done”. The original Linux announcement had mentioned 386 AT clones, but support for the original 386 was dropped a number of years ago. With the release of the final 5.3 imminent, our attention will turn to 5.4 next month. Another month, another security vulnerability affecting the industry. Bluetooth as a protocol comes in several flavours, including the classic BR/EDR (Bluetooth…

Build Brighton Thursday evening is open night. http://buildbrighton.com Cornwall Tech Jam Second Saturday of the month, alternating between Bodmin and Camborne www.cornwalltechjam.uk Thingqbator An IoT-focused makerspace, meeting weekly at The Shed MMU. mcr.thingqbator.org Leeds Hackspace Open night every Tuesday 7pm-late. Open day second Saturday of the month, 11am-4pm. http://leedshackspace.org.uk Huddersfield Raspberry Jam Meet every month at Huddersfield Library, typically the fourth Saturday of each month. Huddersfieldraspberryjam.co.uk rLab Reading Hackspace Unit C1, Weldale St, Reading, Open Sessions Wednesday from 7pm. http://rlab.org.uk Horsham Raspberry Jam Park Side, Chart Way, Horsham. www.facebook.com/hackhorsham Maidstone Hackspace We hold open evenings every Wednesday from 5:30pm to 8:00pm. https://maidstone-hackspace.org.uk Glasgow Makers and Hardware Hackers Mitchell Library, Glasgow. www.facebook.com/groups/115303729096198…

You will usually be logged in as a normal user when using Linux, but some operations require elevated privileges. For example, installing or updating software needs the full access that only the root user has. In the past, the solution was to log in as root, usually by running su (switch user) in a terminal. This has two key disadvantages: it requires the user to know the root password, and once they have run su they can do everything root can. That is why almost all distros prefer to use sudo these days. The effect of using sudo is similar – it enables a program to be run as another user (like su, it defaults to the root user unless told otherwise), but it doesn’t require them to be given…

Send your thoughts to the Linux Format dungeon server at linuxformat@futurenet.com, be picked as Letter Of The Month and win* a 32GB Nitrokey Storage 2! The Nitrokey is worth a cool €149, has 32GB of hardware-encrypted storage, supports hidden volumes, secures your online accounts with onetime passwords, can encrypt emails, files and hard drives and is an open source, open hardware solution. Protected with AES-256 and RSA keys up to 4,096! Learn more at www.nitrokey.com.…

For some, a lightweight distro is one that has a minimal footprint on a computer’s resources (memory, processor and storage), while for others it’s all about the size of the downloadable ISO image. Then there are those who think of lightweight distros as ones they can lug around on a portable USB key. First and foremost, we’ll pick lightweight distros not because of their app selection or their default desktop environment, but only because they identify themselves as such. Secondly, our selection may or may not be frugal in terms of their bouquet of apps, and might not even be light in terms of the size of their ISO. They will, however, be misers when it comes to leaving a footprint on the physical resources of the computer, which is…

Making an old computer usable again is on the priority list of several distros, including some mainstream ones. There are official Ubuntu spins based on the LXDE and MATE desktops, which are designed for hardware that doesn’t have the power to run the main edition. LXLE is another popular LXDE-based distro, but it isn’t as lightweight as the options in this Roundup. If you prefer the Openbox window manager, you could try your hand at WattOS, but it hasn’t been updated in quite a while. The Puppy Linux project produces a number of other variants based on different distros, such as SlackoPup that’s based on Slackware. Digressing a little, the Porteus and Slax distros, that are designed to run from removable media such as a USB flash drive, can also…

Mint’s welcome screen has a few handy hints in its First Steps section. Most notably it would like you to set up System Snapshots, which you should do. Unlike traditional backups, these by default only back up system files, leaving it up to you to back up your home directory. The theory is that the user should have more of a clue about what’s in here and how important it is, so should manage that separately. Launch the Timeshift program from the Welcome screen, choose RSYNC, and choose a schedule and frequency that suit your requirements and disk-space forecast. Mint recommends keeping five daily and five boot snapshots – so you can revert to, say, three boots ago before you broke everything, or yesterday, when all your troubles (guilty conscience?–Ed)…

The Ubuntu-based flavours of Mint tend to get all the limelight, what with all the excitement around new point releases (feed my monkey brain–Ed) every six months and big releases every two. But there’s another edition you don’t hear so much about, which is the release based on the Debian Stable series. Apart from being a nice project, this means Mint has a backup plan in case it’s no longer possible to use Ubuntu as a package base. The current release, LMDE 3 ‘Cindy’, is based on Debian Stretch – the stable edition launched in 2017 and is supported until 2022 – and so has some quite old packages under the bonnet. But with Debian 10 ‘Buster’ now being the current stable release, LMDE 4 will be in the wild…

June was quite the month! As everyone scrambled to get their latest slice of Raspberry Pi, retailers have been rushing to ensure that they have the latest add-on boards and equipment to support the Pi 4. It is the natural order for a Pi release – a new Pi means new add-ons to further hurt your wallet. One of the most prominent issues with the Pi 4 has been the amount of heat it can generate, and so this has been the focus of the latest products. The new Pi 4 can idle at around 50°C and can be easily pushed up to 80°C with heavy loads! Pimoroni has released two cooling products. The Fan Shim was released at the same time as the Pi 4 and has proven to…

You’re not necessarily reliant on USB flash sticks and router-based network connections to share data between your PC and Raspberry Pi. A more straightforward option is available: just hook up an Ethernet cable. Raspberry Pi Model A and B devices with an Ethernet port can be connected to your PC. Once hooked up, you can communicate with the Pi over SSH, copy files using scp or FileZilla as described, and disconnect by removing the Ethernet cable. On Linux, start by installing avahi-daemon. This is a package that includes the zeroconf software needed to detect the Raspberry Pi on your computer: If your main computer is a Mac, zeroconf is baked in. Windows users will need to install Bonjour – this is easily done by installing Skype, iTunes (arrg!–Ed) or Adobe…

Although browsers drove them to the brink of extinction, dedicated RSS readers are making a comeback, thanks in part to Firefox ending native support to read RSS feeds. If you prefer working on the terminal, whether because of the functionality, the speed or versatility, you’ll quickly become enamoured with Newsboat. Forked from Newsbeuter, the MIT-licensed project is available in the software repositories of most Linux distributions such as Fedora, Ubuntu, Arch, Debian and others. As the tool depends on a handful of libraries such as libcurl, stfl. and other lightweight projects like pkgconfig and SQLite3, you can easily install Newsboat by compiling it from source, on the off chance your distribution doesn’t offer it in the software repositories. Even better, you can install it using the Snap package by running…

Did you notice that we’re not using the sudo command to install Termux packages? Remember, pRoot is a userland implementation of chroot, which means its permissions are already reduced to a normal user level. While the default Termux environment is compact by design, you can actually use it to get a full Linux distribution on your device. Or rather, you can use the pRoot utility to do so. Check https:// proot-me. github.io for how to do this. If the graphical app you want is available in Termux’s X11 repo, for example, you should be able to get just that app up and running. But if you’re looking for a variety of programs and/ or a desktop, consider one of the apps designed specifically for this purpose. If this is something that…

Displaying the text-based programs we’ve focused on thus far in a terminal is easy. But you can also install graphical applications using some of the above-mentioned apps. Normally when displaying remote applications over a Linux-to-Linux connection, both of these are running an X Server. This makes it easy to hand off graphics from one machine to another. The issue on Android is that there is no X Server, as it draws its graphics directly to the framebuffer. Most of these apps will give you the ability to ‘remote into’ the Linux instance using VNC. A quick search of the Play Store reveals many, many VNC apps, including the Remote Ripple Pro app (http://bit.ly/ LXF255ripple) from the devs of Linux favourite TightVNC. Alternately, you can install an X Server on your…

Sweet Home 3D LibreOffice Olivia FreeTube Dynamic Wallpaper Editor Cloaker Latte NRedneck Pekka Kana 2 Community Edition INTERIOR DESIGN APP Sweet Home 3D Version: 6.2 Web: www.sweethome3d.com Sometimes it’s not easy to explain your vision for a new room layout using just words. Whether that’s because of your limited artistic skills or the complexity of the design itself, we recommend transferring your thoughts to a 3D plan using Sweet Home 3D. It is of inestimable value since there are virtually no other open source applications of this kind. At first, this application seems to be just a specialised version of a vector editor, where you can draw your room and arrange smaller rectangles that act as furniture items or appliances. It still requires spatial thinking to imagine how things will…

Linux expects the stack pointer (RSP) to be maintained on 16-byte boundaries in memory. That means that the hexadecimal (base 16) value for RSP should end in 0. This seems to only be required for Streaming SIMD (Single Instruction Multiple Data) Extensions, a technique that allows a vector of data to be operated on by a single instruction – useful for real-time graphics. We don’t use SIMD in this tutorial, but this seems to be best practice. Linux also expects that the base pointer (RBP) will be pushed to the stack at the beginning of a function and removed at the end. This seems to not be required, but is helpful for debuggers. Again, it seems to be best practice. These coding practices are implemented by the gcc C compiler…

Maybe you’re stuck for ideas for your pixel art creation, or perhaps you need a little inspiration. Either way, you could always try searching Google for pixel art templates. There are plenty of free templates available with grid-lines and numbered boxes, which will be helpful in creating your lists in Python. You can mirror these by counting the rows/columns and adjusting your Python list to match. Our Creeper and Steve heads were 8x8, but there’s no reason you couldn’t use much bigger grids. You could quite easily adjust this to 12x12, for example, by adding four more numbers to each row of the array. Just don’t forget to also add four more lines to the grid – you’ll need to extend it by the same amount of lines going down…

THE LXF LIBRARY Advanced Bash Scripting Guide Go further with shell scripting. Bash Guide for Beginners Get to grips with the basics of Bash scripting. Bourne Shell Scripting First steps in shell scripting. The Cathedral and the Bazaar Eric S. Raymond’s classic text explains the advantages of open development. The Debian Book Essential guide for sysadmins. Dive Into Python Everything you need to know. Introduction to Linux A handy guide full of pointers for new Linux users. Linux Dictionary The A-Z of everything to do with Linux. Linux Kernel in a Nutshell An introduction to the kernel written by master hacker Greg Kroah-Hartman. The Linux System Administrator’s Guide Take control of your system. Tools Summary Overview of GNU tools. GNU Emacs Manual Six hundred pages of essential information! Producing Open…

“Right, that’s it. I’m leaving. But don’t worry, it’s only for a couple of months. After 70 issues and several hundred thousand words of hard Linuxing, I’m taking a short break to ponder life’s great mysteries: Why is middle-click pasting broken in KDE? Why does my monitor not wake from suspend 10 per cent of the time? What exactly does Brexit mean? Besides that I’ve got several little Pi projects to be resurrecting and hacking on with, and it’ll be nice to be doing this as a hobby and not a duty. Just keeping up with Linux developments is pretty much a full-time job. Even in five years things have changed a lot; the phrase “year of Linux on the desktop” has shifted from the dream category to the meme…

“With the release of virglrenderer 0.8.0, getting accelerated OpenGL within a virtual machine (VM) has made a big leap forward. Not only does virglrenderer offer full virtualisation, when it is used, for example, by QEMU as a consumer, it also provides virgl_test_server as a means for a more lightweight separation of the host and OpenGL client software. The latter was originally only meant to be used for testing purposes; however, it has been improved so that it can now also be used to provide OpenGL acceleration within Linux containers. Within this latest development cycle, a special focus was put on providing OpenGL in guests running on OpenGL ES hosts. It is now possible to run most software that require up to OpenGL 4.3 in guests that run on hosts offering…

A debate about the “elephant in the room - the Linux kernel’s inability to gracefully handle low memory pressure” saw various comments that recent work on PSI (Pressure Stall Indicators) and other infrastructure wasn’t enough to prevent a continuing annoyance of stuttering behaviour under memory pressure. Anup Patel posted several revisions to “KVM RISC-V Support”, a patch series which is now destined for upstream, having been blessed by the KVM maintainer. The associated discussion lead to some process debate around how to document which mailing lists should be used when posting KVM-related patches in general. BenH (Benjamin Herrenchmidt) posted patches implementing support for the NVMe controller present in Apple’s latest generation of Macs featuring the T2 chip. The controller has a number of quirks that differ from the NVMe spec,…

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 visiting deity testing out Arch Linux), 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…

BionicPup uses a custom installer and supports two installation mechanisms. The default frugal mechanism copies files inside a partition which holds another distro, while the full option takes over the entire partition and is recommended only for older machines. The installation process is rather unconventional and might even intimidate first-time users, but every step is well documented and easy to follow. antiX also uses a custom installer that’s verbose enough to be operated by inexperienced users, despite the fact that it uses GParted for partitioning. That said, not many people would be dual-booting an old machine and the installer is a charm to use if you’re installing antiX to the entire disk. The installer offers the option to encrypt the partition and will install the desktop you are currently running…

Olivier Crête leads Collabora’s multimedia team and has been working on GStreamer since 2007. As far as we know, this is the only Linux software to reference the classic western The Good, the Bad and the Ugly in its package naming scheme (look it up). Olivier has also worked for the Gentoo project for the best part of a decade, which we found odd because other than that he seemed pretty normal. He was good enough to share some of his erudition with Jonni the one time we let him out last year to attend the Linux Foundation’s Open Source Summit in Edinburgh. Check out Olivier’s ‘GStreamer for Tiny Devices’ talk from the same conference a year earlier at http://bit.ly/lxf255gstreamer1 . Olivier is also a veteran of instant messaging, having…

QEMU is not a bad emulator, especially when run with KVM acceleration on a somewhat recent workstation. It is, however, sorely lacking in the graphics department – if you need high graphics performance, look elsewhere. Should you feel like performing significant Fuchsia development, running the product on real hardware is definitely recommended. As of this writing, Google sadly doesn’t support single board computers based on 64-bit Arm processors. Instead, only the following three bits of hardware are officially supported: Acer Switch Alpha 12, Intel NUC, Google Pixelbook Tests by ArsTechnica revealed generally good performance on the Pixelbook, at least as long as a release build was deployed; with debug builds, the GUI stack was quite slow. Should you be able to get your hands on one of these, simply follow…

Google chose to implement capability-based programming via token objects. In principle, an application which wants to use a specific service first asks the operating system for a token object; this is an (ideally) unmodifiable element which acts as a kind of passcode and furthermore uniquely identifies the program towards the API. Actually, API interaction takes place in a pattern not dissimilar to the one known from SGS Thomson’s CUBE environment. Most if not all API calls take the object and pass it to the operating system on every single invocation.…

Anvil is much more than just a tool to control a Raspberry Pi. Anvil has many more features, such as data tables to record data, email, user authentication, Google and Facebook APIs, and Stripe to take payments. What does this all mean? Well, using Anvil we can build an app to enable payments to be made, recorded into a data table and then visualised using the built-in graphing library, plotly. Anvil apps can be shared using a private URL for internal use, or via a public short URL that can be shared on social media. Anvil can also work with devices that deal with web data, for example ESP8266 and ESP32 boards. These boards are cheap and using low power, they can gather data in the field and then send…

Newsboat itself doesn’t ship with an anonymising feature, so all your browsing is susceptible to snooping and the inherent risk of connecting to the internet. If you’re interested in protecting your identity online, you must connect Newsboat with a proxy server. You can even configure it to work with Tor, but the process might be slightly more involved depending on your distribution of choice. Another issue with installing Tor using the software management tool on your distribution is that although most distributions ship it in the software repositories, it isn’t updated as often, so the latest version might not be available for a long time. But this is a distrospecific problem, and might not be a factor for all users. Once Tor is running and socksport is set to the…

To install Flatpak in older versions of Ubuntu: $ sudo add-apt-repository ppa:alexlarsson/ flatpak $ sudo apt update $ sudo apt install flatpak Sometimes you may see an app appear twice or more when searching for software. Click each entry to check the version number and source – some will be snaps sitting alongside versions held in the main Ubuntu repositories. If the Software & Updates box goes grey when you attempt to tweak the settings on the Ubuntu Software tabs, switch to the Updates tab and untick any of the boxes. Enter your password, then retick the box and return to the tabs.…

The actual process of rooting your device is beyond the scope of this article – and the prior LXF piece on the subject, while it contains some good information, is a little outdated at this point. So if you’re looking to give rooting a try, here are some helpful resources. The first place you should be looking is the XDA Forums (https:// forum.xda-developers.com) – not for tools necessarily, but rather information. The knowledgeable folks there have created some very detailed guides on everything from installing alternative ROMs onto your device to replacing your Android OS entirely with Linux. There are two things you should look at for your specific device model: 1 The directions and any caveats to rooting your phone. Guides on XDA can be a little lengthy, but…