Linux FormatJune 2023的目錄

It was a great experience to attend the Collabora Productivity Hackfest and talks in Cambridge. Not just to get up to speed on the latest online office technologies – which you can read about on page 90 – but to meet and encounter the depth of enthusiasm and experience from its startlingly wide array of developers from literally all over the world. That’s always been the strength of the open source community – it’s willing to draw upon the best and most active developers no matter where they may be working. Something that seems to have caught on in recent years… Equally, the spirit of hacking lives on in the truest sense, with hackfests still a key way of driving innovative, collaborative development. So, we come to our latest hacking…

"There is an old saying: if things aren’t broken, don’t try to fix them. This is especially true in IT, where some of the systems we rely on every day have been in place for decades. These systems are ingrained in their organisations, and trying to replace them without good reason may end up being a career limiting decision. However, there are many things in our IT systems that can be quietly going wrong. Here, I’m talking about database queries. A query is used to retrieve a set of data from your database, or carry out an action on it. A query can help your customer find what they want, understand information, or deliver the result they need. Queries deliver what you want from your data over time. Yet what…

On 30 March, Google engineers emailed the Vger Linux kernel mailing list, asking for comments on a series of patches to their KVM-CPUFreq driver. This is part of an overall plan to improve the dynamic voltage, frequency scaling behaviour and task placement within virtual machines. Google’s own David Dai cautioned that these patches aren’t ready to land in the upstream kernel, but initial benchmarks are very promising, with an Android VM on a Chromebook performing 19% more efficiently as a weighted total. The greatest performance was seen when writing (+29%) and video editing (+45%). Google’s new patches hugely improve virtual-machine performance but so far tests have only been conducted on a Chromebook and Pixel 6.…

"I try to keep certain contentious topics out of this column as debate can quickly become heated. Yet we can’t live isolated from the real world, where terrible things happen that can impact all of us, even in the world of open source software. Especially in these times of conflict. This was the case when a developer associated with (sanctioned) Russian company Baikal Electronics tried to post patches to the Netdev Linux networking development list. His post was greeted tersely by a maintainer: “We don’t feel comfortable accepting patches from or relating to hardware produced by your organisation. Please withhold networking contributions until further notice.” The thread ended there, but not the follow-on discussion about the potential implications. There does not appear to be an official policy of the Linux…

IPfire Alpine Linux VyOS Endian ClearOS Nate Drake is a tech journalist specialising in cybersecurity and retro tech. HOW WE TESTED… Firewall distros are designed to do one thing very well, so they don’t have advanced GUIs or bloatware – this means they functioned perfectly well in a VirtualBox VM with a 1GHz CPU, 1GB of RAM and an 8GB hard drive. We noted that some firewall distros, such as IPFire and Alpine Linux, can run directly in RAM but went through the install process to preserve network configuration and store updates. Where possible, if a firewall distro offered a web interface, we simulated this using a VM running Ubuntu 23.04 using VirtualBox’s Internal Network feature. Command line lovers will be pleased to learn there’s no requirement to use the…

We’ve touched on IPFire’s segmentation of your network into Green and Red zones for trusted and untrusted devices. It also supports creating a blue DMZ to isolate internet servers from the rest of your network. It uses Suricata IDS to prevent attacks, replacing the previous tool Snort. Alpine Linux claims that all userland binaries are compiled as Position Independent Executables (PIE) with stack smashing protection, making the OS less vulnerable to buffer overflow or zero-day attacks. It also uses the musl libc library, which is a leaner (and arguably more secure) version of glibc. VyOS uses Minisign as well as PGP to verify the integrity of its downloads. The developers regularly issue new security releases. VyOS is also the only distro we reviewed that supports MACsec, which encrypts traffic between…

Hacking is cool. Not the kind of hacking you usually get up to on your Linux machine – tweaking open source code to wring the last ounce of performance from an ancient program or adding new functionality to suit your needs. No, we’re talking about the other kind of hacking. Think black hoodies and world maps. Angelina Jolie and Jonny Lee Miller fleeing the Feds in the dead of night after some illicit intrusion or other. Hackers are the modern equivalent of cat burglars, breaking into high security areas to make off, unseen, with a priceless portrait or the contents of your secret vault. They blend into the background while drinking cocktails with their targets, and live the high life thanks to the proceeds of their victimless crimes. Of course…

It’s a rare piece of code that never requires patching to fix some flaw or other that allows users to do what they were never meant to do. Exploits can be as simple as checking out plain text password files in an unprotected directory, or inputting something akin to the Konami code. It can be spamming a password field until it breaks, or writing more data to a memory buffer than it can hold. Hackers have been hacking since before the first computers were networked together with bits of string and sticky tape. Generally, this involves poking things until they break, and then poking them again. Occasionally, it involves the careful inspection of code to see whether there are any obvious flaws that developers have missed. This is one of…

OUR EXPERT Mike Bedford hates to admit it, but he had his first experience with ALGOL before it fell out of favour, so getting to grips with it again was a trip down memory lane. I nthe latest instalment of our series on classic programming languages, we’re turning the clock all the way back to 1958. And that takes us to the earliest days of highlevel languages. If we ignore a couple of languages that few people have even heard of today, and which probably weren’t too influential, only FORTRAN came earlier, and by just a year. The other classic high-level language of the era, COBOL, wouldn’t be released until the following year. The 1958 creation in question is ALGOL, and we have to admit that it never took the…

OUR EXPERT Michael Reed has been messing around with computer music since the late ’80s. Fortunately, none of these early efforts have survived. Tracker music first arrived in the early ’80s on the Commodore Amiga series of T computers thanks to a program called The Ultimate Soundtracker. This music application and its clones laid down the foundation for the entire tracker music scene, a scene that is still alive today. Because tracker files contain the note data that makes up the song alongside the sample data for the instruments, it was quickly embraced as an ideal format for game music as well as by amateur musicians who wanted to share their music. Right from the beginning, music trackers attracted a huge community, and it helped that the format was…

LXF303 will be on sale Tuesday 30th May 2023 Climbing the ALPs Finally something on OpenSUSE! Just in time to see it drop its traditional distro release and switch to a containerised system. Searching here and there Desktop search has had a chequered history but we’re here to ensure you can search as fast locally as online. Learn a coding language We size up the best alternative coding languages to see which you should be learning to get ahead with application creation. The Microsoft Linux cloud We make the most of the free Azure cloud and see what we can get up and running from the Microsoft Linux offering. Contents of future issues subject to change – we might have been whisked off to pastures new!…

David Rutland For Christmas 1997, my cousin John and I both found mobile phones under the tree. The networks used standard passcodes, and I exploited this flaw to abuse John’s voicemail – recording offensive messages, which got him into trouble with his parents. Les Pounder It was the 1990s and I had just transferred to a new school, which had a pool on the roof. Anyway, we tried to hack the planet with a rabbit; they fought back with a flu shot. Wait, no, this is the Hackers movie. Never mind. Mayank Sharma My favourite moment with the distro was back when it was called BackTrack; to crack a WPA2-PSK Wi-Fi password. Sure, it didn’t take much doing, but to see the Wi-Fi key pop up out of thin air…

In mid-March, Docker sent an email out to all users who had created an “organisation” announcing it would be “sunsetting” its Free Team plan. This didn’t affect users who had a free, personal account, but sparked a brief online panic that this would effectively mean open source organisations would be deleted if they couldn’t pay the requested $240 per year. The email contained a link to a PDF containing more info but it was thin on details of what would happen to teams who refused to pay. It also wasn’t clear if others would be able to squat on projects’ domains if their accounts were removed for non-payment. A week later on 16 March, an apologetic post appeared on the Docker blog admitting they did a “terrible job” of the…

FINNIX 125 Finnix is a self-contained, bootable Linux CD distribution (live CD) for system administrators. It’s based on Debian and now includes a mixture of packages from both the stable and unstable repositories. The latest version uses kernel 6.1 and comes with new packages including 2048, aespipe, iperf3, ncdu, netcat-traditional, ninvaders and vitetris. There’s no GUI but, on the plus side, the ISO is less than 500MB. It can be booted live to diagnose issues. You can download it from www.finnix.org. OPENMANDRIVA 23.03 OpenMandriva is a fork of ROSA, a Russian distro, which itself was a fork of the original Mandriva Linux. The ROME version for personal users follows a rolling release model. The latest default snapshot includes the KDE Plasma Desktop, but there are also images with the LXQt…

Linus Torvalds announced Linux 6.3-rc6, noting, “It’s Easter Sunday, which means that we’re all about to gorge on mämmi. (Right? You do have your carton of mämmi ready to go, don’t you?)” For those who aren’t Finnish, apparently this is a traditional orange-flavoured dessert made from water, and rye flour. Things do seem to be calming down towards the end of the 6.3 cycle, meaning that we should have a final 6.3 release imminently and then will come the opening of the merge window (period of time during which disruptive changes can be merged) for what will be the 6.4 kernel series. We will have a full summary of the features queued up for that cycle once the merge window closes, next issue. “The main concept is still to throw…

OUR EXPERT Les Pounder is associate editor at Tom’s Hardware and a freelance maker for hire. He blogs about his adventures and projects at http://bigl.es. YOU NEED Raspberry Pi 4 or 400 USB 3 flash drive 16GB microSD card Official Raspberry Pi power supply For many of us, booting the Raspberry Pi from microSD is more than enough, but for those of us who want speed, we need USB. It has been possible to boot the Pi from USB for some time, but in recent months it has become far easier thanks to the official Raspberry Pi Imager. The imager now supports flashing the bootloader by writing a special configuration to a microSD card. This then programs the bootloader to look for USB boot drives as a priority. In this…

Credit: https://github.com/muesli/duf OUR EXPERT Shashank Sharma is a trial lawyer in Delhi and an avid Arch user. He’s always on the hunt for affordable geeky memorabilia. As much as we love rolling release distros, and even LTS releases, for that matter, their one big downside is that they never cause you to assess your files and discard the old and useless ones. You ultimately end up with a full disk, with no idea of how it happened or what to do about it. Or maybe you’re far saner than us and would never demean your hard disks by hoarding files. Your Linux distro offers several tools and utilities out of the box to help assess disk space usage, and there are various other command-line and graphical applications that can also…

OUR EXPERT Karsten Günther rolls out the list of G’MIC filters to entertain and educate. Most photographers are familiar with this problem: an otherwise great picture is spoilt M by a detail that almost cancels out the effect. For example, a car or a sign in a landscape photo, a spot on the lens… Usually, it helps to correct the corresponding areas with the Clone or Heal tool, or with Resynthesizer (LXF301) via the Heal Selection filter. Both methods have their limitations: manual repair quickly reaches its limits with smooth surfaces, strict structures and large areas, but Resynthesizer also often has problems. Manual methods lack options for rotating, distorting or scaling transferred material before it’s reintroduced into the image. Resynthesizer uses such small patches that this is often not…

"This column will be my last in these pages – for now, at least. For the past five years, I have written here about using Linux in business. My core message has been that we should design, build and maintain Linux systems that are secure and available. That focus shouldn’t change just because I’m no longer writing about it, of course. Those three words – “secure and available” – sum up what pretty much every business wants from its Linux servers. I’m extremely proud to be part of the open source revolution – and you should be, too. Back when I started working in IT, there was no such thing. The idea of legally sharing software without any charge was completely unheard of. Since then, open source has taken the…

"New generations of Arm Mali GPUs have replaced their old model of job management – where the Linux kernel is responsible for resolving dependencies and scheduling jobs – with a command-stream design in which GPU firmware is in control of execution. This is a fundamental shift not only in how userspace submits jobs and handles synchronisation, but also in the design of the kernel driver and DRM’s core scheduler architecture. We now get to work with a completely new uAPI (almost nothing shared with the old one), a new scheduling logic and a new MMU/GPU-VAmanagement logic. This leaves us some driver initialisation boilerplate, the device frequency scaling implementation and the power management code, which is likely to differ, too, as some of the powermanagement is now done by the firmware.…

Q Chi cken and eggcryption I have Pop_OS installed on my Surface Pro 3. During installation, I neglected to uncheck the option to encrypt the disk. Now when I turn on the tablet, I must have a keyboard attached in order to get past the first login screen as no virtual keyboard is made available. The second login screen does make the virtual keyboard available. Is there a way to disable the disk encryption? Or, is there a way to activate a virtual keyboard on this first login screen? My whole purpose in installing Pop on the Surface Pro was to take advantage of the portability of the tablet without a keyboard. The OS runs blazing fast on this old tablet computer. Hank Collins A This occurs because unlocking your…

IP Fire’s setup wizard is very intuitive, but if you do run into trouble, there’s a simply laid-out wiki, which explains more about the firewall itself, basic setup, the web interface and how to customise your install. We were particularly impressed by the tutorials section, which contains links to YouTube videos giving easy to understand explanations. Alpine Linux also has an in-depth wiki. It covers installation and a FAQ. There’s also a tutorial section for post-install tasks such as downloading add-ons and creating new user accounts. The cheat sheet Comparison With Other Distros deserves a mention as it lists commands in popular flavours of Linux such as apt update and the equivalent for Alpine (apk update ). VyOS’s technical documentation is powered by Read the Docs and has a very…

Les Pounder works with groups such as the Raspberry Pi Foundation to help boost people’s maker skills. As I write this we are one quarter of the way through 2023 and the sun is starting to shine for a little longer each day. Things are starting to look a little brighter for Raspberry Pi stock, too, but the board everyone wants, Raspberry Pi 4, is still virtually unobtainable. I keep an eye on Rpilocator and can see that Eben Upton’s predictions of more stock filtering into the channels is coming true. Right now, if you need a Raspberry Zero W or a Raspberry Pi 3 Model A+, you are in luck as these are in stock at various retailers around the globe. According to Rpilocator (https://twitter.com/rpilocator/ status/1637917163754 254340), the last…

Part Six! Subscribe on p16 and access all the parts now! OUR EXPERT Les Pounder is associate editor at Tom’s Hardware and a freelance maker. He blogs about hacks and makes at http://bigl.es. YOU NEED Robot build from part five Pi camera Code and more: https:// github.com/ lesp/Linux-Format-Robot/ archive/ refs/heads/ main.zip At the end of part five, our robot had been connected to the Anvil web service and was successfully controlled via a web interface. In this final part, we will unleash the robot in autonomous mode, where it can use its sensor to navigate the world around it. We’ll refine our motor.py module to add further debug features, before finally adding a special sliding mode for our mecanum wheels. We’ll also take a quick look at a video-streaming Python…

OUR EXPERT Nick Peers has been playing around with computers for over 30 years, and has been dabbling with Linux for the best part of a decade. When it comes to time-saving tools, the text expander is one of the most universally W useful. Everyone has to type words, phrases and sentences, but smart text expander tools such as Espanso do more than simply enable you to save time entering repetitive information – you can also use it as a universal autocorrect tool, or to quickly populate an email with a specific template, insert system information such as your IP address or even quickly embed bits of code with the minimum of fuss. Get set up Espanso comes in two flavours depending on whether you’re running the X11 or…

OUR EXPERT has been a fan of the open source methodology for over two decades and uses Linux and other tools where possible. In his spare time, he enjoys listening to music and reading. QUICK TIP More information about the Greaseweazle can be found at https://github. com/keirf/ greaseweazle/. Let’s take a trip down memory lane to when your author was still a child. One L glorious summer day, after a short car ride and £1,600 (that’s £3,400 in 2023 pounds) spent, we returned home with a couple of rather large boxes. Inside these boxes were a keyboard, mouse, cables, monitor and an Acorn A5000. This glorious computer started an interest in computing that continues to this day, having already spanned the best part of 30 years, and shows no sign…

System Monitoring Center Version: 2.8.0 Web: https://github.com/ hakandundar34coding/systemmonitoring-center Mayank Sharma isn’t a fan of cryptos, but wonders whether he needs to give them another look, especially when he sees popular, regulated banks crumbling around him. Most Linux distros ship with decent default system monitoring tools that enable you to M graphically monitor how your system is using hardware resources. The issue is that they’re pretty basic in terms of reporting. They only track and report the parameters that would suit the average user. For instance, while you get processor usage with a default tool, they don’t report the fluctuating CPU frequency. That’s where System Monitoring Center shines. The tool is pretty comprehensive in its monitoring, tracking all the essential system resources in great detail. The app is available in the…

OUR EXPERT Andrew Smith is a software developer for NHS England. He enjoys video gaming and started coding in C/C++ in 1997 on a Borland C++ for DOS compiler. QUICK TIP You can find the full source to this project at https:// github.com/ asmith1979/ lxf302/. This month, we are continuing with the 3D chess program that we started in LXF301. T We’re creating a basic mouse-driven menu system to be shown at the start of the game program and adding game controller support. The original source code for the 3D chess program can be downloaded or cloned from https://github.com/ stevenalbert/3d-chess-opengl. Some aspects of the original code have been modified for this tutorial. We used a PC-compatible Xbox One controller to test and implement the functionality, but other PCcompatible game controllers…