Innehållsförteckning för October 2024 från Linux Magazine

Dear Reader, Are fortunes changing for Google? Many observers think so, but trillion dollar companies have ways of making problems go away. It does seem like they are on a bit of a losing streak when it comes to government tolerance of their anti-competitive behavior. The EU has been leveling fines against Google for years, and last year, the European Commission issued a formal antitrust complaint, suggesting that breaking up the company might be the only remedy [1]. Earlier this year, the EU began investigating Google under the new Digital Markets Act [2], which is designed to prevent gatekeeper companies from controlling their markets. The EU deserves credit for their diligent pursuit, but because Google is a US company, the recent antitrust finding by the US District Court of DC…

Speeding Up the Dentry Cache Linus Torvalds wrote an experimental patch intended to speed up filesystem operations, specifically the directory entry (dentry) cache. However, he didn’t really like his own patch – even though it worked. He hoped one of the kernel developers might do it better. The dentry cache is a lookup table that sits in RAM and is used by the rest of the kernel to identify exactly where a desired file or directory is located on disk. Whenever you open, read, or edit a file, or anything like that, you use the dentry cache. Typically, you really want that dentry cache lookup to be as fast as possible. You don’t want to sit around waiting for your file to open. Especially if “you” are not a person…

“What I don’t know won’t hurt me,” as the saying goes, but the reverse is true for my wireless network. What are all my household gadgets doing? After all, no newly released device seems to be able to manage without a wireless network connection nowadays. Or are there actually some devices that I don’t even know about? This definitely worries me and keeps me tossing and turning in my sleep. On top of that, I am interested in more than the current situation. Curious by nature, I would like to know how long a device, once discovered, has been operating on the network, when it joined the network, and whether it is permanently active or occasionally lets its assigned IP address lease expire and then picks up a new one…

Cyclical Redundancy Checks have been around since the 1960s and still exist today as a means for verifying the integrity of a file. The CRC32 checksum variant has existed since the 1990s. Although the CRC32 checksum method is no longer considered safe for security purposes (see the box entitled “Not a Security Tool,” a CRC32 check can still identify other forms of random errors that can occur during data transmission or storage. cksfv (short for “Check Simple File Verification”) [1] has lived a quite admirable lifetime as a tool for checking data integrity using CRC32 checksums. A new version (v1.3.15) appeared in 2020 after a gap of 11 years [2]. Today even the project’s developers want to be sure everyone knows cksfv should not be considered a replacement for more…

#286/September 2024 Git Ready The Git version control system is an integral part of the Linux environment. If you’re looking for a better foundation in Git, or if you already know the basics and are ready to start building Git into your own custom apps, we’ll make you Git ready. On the DVD: openSUSE Leap 15.6 and Tails 6.4 #285/August 2024 Kernel Expoilts Is Linux secure? Only if you keep up with the patches. This month we take a close look at how intruders attack unsafe versions of the Linux kernel through known and well-publicized exploits. We’ll show you how to set up your own out-of-date kernel to practice on, and we’ll introduce you to some of the tools and techniques attackers use to gain root access. On the DVD:…

Available Starting October 4 Preview Newsletter The Linux Magazine Preview is a monthly email newsletter that gives you a sneak peek at the next issue, including links to articles posted online. Sign up at: https://bit.ly/Linux-Update…

Large language models (LLMs) such as the ones used by OpenAI’s [1] ChatGPT [2] are too resource intensive to run locally on your own computer. That’s why they’re deployed as online services that you pay for. However, since ChatGPT’s release, some significant advancements have occurred around smaller LLMs. Many of these smaller LLMs are open source or have a liberal license (see the “Licenses” box). You can run them on your own computer without having to send your input to a cloud server and without having to pay a fee to an online service. Because these LLMs are computationally intensive and need a lot of RAM, running them on your CPU can be slow. For optimal performance, you need a GPU – GPUs have many parallel compute cores and a…

In the early 2010s, Linux had already begun conquering data centers, and it was on the path to becoming the standard operating system for servers. At the same time, another data center trend emerged: Virtualization. To keep pace with the development of virtualized infrastructures, networks had to go virtual, too. Software-defined networks (SDNs) were the first step toward network virtualization. The Open Networking Foundation was founded in 2011 to further disseminate and standardize SDNs. Open vSwitch found its way into the kernel in 2012, the same year that VMware bought SDN pioneer Nicira. The pace of development was fast – too fast for the Linux kernel. Network technology requires high performance, which for Linux means that it must be part of the kernel. Code changes to the kernel often take…

Language Skills Last month I talked about low-level assembly and machine languages and the fact that assembly was a mnemonic representation of the ones and zeros of machine language. This month I will discuss what a high-level language is, why they were invented, and why people should still learn some machine/​assembly level language. Machine/​assembly-level languages (hereafter just called “machine language”) were very slow and tedious to program. You typically had to code a lot of statements even to do the simplest things. Even simple statements like A=B+C in a high-level language might take 10 or 15 machine-language statements, and they were prone to mistakes on issues such as register overflow – which might need instructions to test for and correct overflow and which the machine-language programmer might forget to code.…

Sparkling gems and new releases from the world of Free and Open Source Software Turn-based strategy game The Battle for Wesnoth October 2, 2005, marks the first time the NFL played a regular season game outside the United States when the Arizona Cardinals defeated the San Francisco 49ers 31-14 in Mexico City. It’s also the day that David White and a team of eager coders made the initial release of The Battle for Wesnoth available to the viewing public. The game itself is loosely based on the Sega Genesis classic Master of Monsters. Play is turn-based, across a hex map. The world of Wesnoth is extremely Tolkienesque with Men, Dwarves, Elves, Orcs, and Goblins. Readers can also imagine my amusement upon finding that the races even include the reptilian Drakes.…

Users, developers, and vendors meet at Linux events around the world. We at Linux Magazine are proud to sponsor the Featured Events shown here. For other events near you, check our extensive events calendar online at https://www.linux-agazine.com/events If you know of another Linux event you would like us to add to our calendar, please send a message with all the details to info@linux-magazine.com All Things Open Date: October 27-29, 2024 Location: Raleigh, North Carolina Website: https://2024.allthingsopen.org/ All Things Open is a technology conference focusing on the tools, processes and people making open source possible. Our sophisticated and diverse audience is a technical one that includes designers, developers, decision makers, entrepreneurs and technologists of all types and skill levels. SeaGL 2024 Date: November 8-9, 2024 Location: Seattle, Washington Website: https://seagl.org Founded in 2013,…

Ubuntu 24.10 to Include the Latest Linux Kernel Canonical announced that Ubuntu 24.10 will be the first release to ship with the latest upstream kernel. That means “Oracular Oriole” will come with Linux kernel v6.11. Previously, Ubuntu shipped with kernels that would soon reach end of life (EOL), which was driven by Canonical’s need to always ship what they knew would work and had been sufficiently tested, vetted, and updated. According to the Ubuntu Kernel Engineering Director, Brett Grandbois (https://discourse.ubuntu.com/t/kernel-version-selection-for-ubuntu-releases/47007), the old policy was a conservative “wait and see” approach, which guaranteed stability on the appointed release day but proved unpopular with consumers looking for the latest features and hardware support. Under the new policy, Grandbois states, “Ubuntu will now ship the absolute latest available version of the upstream Linux…

Ever since package managers added automatic dependency resolution, installing software in Linux has been easy. The greatest difficulties arose from attempts to use different package formats, such as Debian’s Alien. These attempts were never fully successful and were widely ignored. However, with the popularity of universal formats such as AppImage, Snap, Flatpak, and web applications, package management has become more complex, with each format using its own commands for administration. Formerly known as fpakman, bauh [1] is designed to simplify package management by using a single interface for all formats. In addition, bauh is one of the easiest interfaces available for package management either on the desktop or at the command line, despite the fact that some of the interface’s details need to be improved. Currently at release 0.10.7, bauh…

PiJuice HAT for battery-powered Pi Zero A Raspberry Pi Zero (W) can require upwards of 100mA – depending on what it is doing. This may not sound like much at first, but given a standard industrial LiPo cell rated at 2,200mAh, that computer won’t even last a day. This makes it all the more important to use the battery’s energy sparingly. HATs (Hardware Attached on Top) by PiJuice, which have been around for some time, have the circuitry to help you do this. In this article, we take a look at the PiJuice Zero [1], a pHAT that is optimized for the Raspberry Pi Zero (Figure 1). Use Cases But first, let’s take a brief look at potential application scenarios for a power management HAT: A Raspberry Pi that is…

Linux Magazine is looking for authors to write articles on Linux and the tools of the Linux environment. We like articles on useful solutions that solve practical problems. The topic could be a desktop tool, a commandline utility, a network monitoring application, a homegrown script, or anything else with the potential to save a Linux user trouble and time. Our goal is to tell our readers stories they haven’t already heard, so we’re especially interested in original fixes and hacks, new tools, and useful applications that our readers might not know about. We also love articles on advanced uses for tools our readers do know about – stories that take a traditional application and put it to work in a novel or creative way. We are currently seeking articles on…