Tabla de contenidos para December 2020 en Linux Magazine

Dear Reader, This month, the Wisconsin state government declined to pay the refundable tax subsidies to Foxconn, the Taiwanese conglomerate that arrived in Wisconsin in 2017 with the promise of a plant that would make LCD TVs and monitors and employ 13,000 people. It seems this “project” never did really get off the ground. The original vision of 13,000 workers soon scaled down to 5,200; then it plummeted still further as no one seemed to have a vision for what these people were going to do. After it became clear that it wouldn’t be profitable to make LCD screens (something neither the company nor the state seriously investigated before announcing the deal), Foxconn searched for other uses of the gigantic space they had already built. Casting about for an endeavor…

Shared Processes with Hyper-Threading Joel Fernandes wanted to speed up hyper-threading by making it possible for processes on the same CPU that trust each other to share hyper-threads. Hyper-threading is Intel’s proprietary form of hardware-based multithreading. Generally in Linux and other operating systems (OSs), the OS is responsible for switching rapidly between processes, so everything on the system seems to be running at once. Hyper-threading does this at the hardware level, saving time for the OS. But the OS can still interact with Intel’s hyper-threading features, so folks like Joel can try to eke out performance improvements. Joel specifically wanted to improve Peter Zijlstra’s “core-scheduling” patches, which Peter famously hates the way one hates slowly pulling out their own fingernails. He actually did this once. No, not really. However, the…

KDE and its Plasma desktop are a paradox among Linux distributions. While they regularly poll as the most popular desktop environment, preferred by just under a third of users, a majority of desktop environments use Gnome technology. Consequently, for many users, KDE and its Plasma desktop are largely unknown. Upon encountering KDE Plasma for the first time, I’ve heard many Gnome users say: “It’s like an entirely different operating system.” Founded in 1996 by Matthias Ettrich, KDE was among the first fully-loaded desktops for Linux. Before that, Linux’s graphical interfaces were limited to window managers. The name originally stood for “Kool Desktop Environment,” but it quickly became just the K Desktop Environment. Several years ago, the KDE project reorganized into a group of subprojects. The name KDE now applies to…

I’m not very good at sorting things sensibly and then finding them again – both in my office and on my computers’ filesystems. For the latter, at least I have electronic help in the form of tools like find and, more recently, fd. The find command existed on Unix systems long before Linux was invented – in fact, it’s older than most of the people who use it. On many of my systems, there is a directory named/test where I try things out. Anything that proves useful is sent to Git; the rest just hangs around gathering dust until the cron job in Listing 1 sweeps it away without write access after 365 days. While doffing a hat to the now impressive power of the GNU implementation of find [1],…

The versatile tools of the Linux environment can help you with more everyday problems than you could ever think of listing. For most of us in the Linux space, it is especially appealing to see the old-school utilities of the Unix/Linux command-line environment at work on new-age solutions for the cloud era. One popular terminal tool called rsync is especially adept at aiding in backup and archiving. This month, we deploy rsync in a most contemporary context: backing up a shared-hosting website. Elsewhere in this month’s Linux Voice, we explore tuptime – a tool used by professional admins to track uptime statistics, and we drill down into Asciidoctor, an inspired application that transforms AsciiDoc files into HTML5, DocBook, or PDF format.…

If a Linux system has been running for a long time, this is definitely proof of its stability, but – depending on the distribution – some updates might be waiting to install. Conversely, if the system reboots very frequently, there may be a configuration error – or maybe a hardware component is slowly deteriorating. On a workstation computer, such restarts are quickly noticed, but not necessarily on a remote server that is running quietly and well away from the action. How long a system has been running continuously can be determined at the command line by a call to uptime. But you might also want to try tuptime [1], a similar tool whose name is based on a contraction of “total uptime.” It outputs far more information, including valuable information…

#240/November 2020 It's Alive Build a whole operating system? Well maybe not a Linux, but if you're interested, you can implement the basic features of an experimental OS using resources available online. We can’t show you the whole process, but we'll help you get organized and take your first steps. On the DVD: Linux Magazine 20th Anniversary Archive DVD #239/October 2020 Build an IRC Bot IRC bots do the essential work of coordinating and forwarding chat messages on the Internet. This month we show you how to build your own custom bot – and we give you an inside look at how to work directly with IRC. On the DVD: Debian 10.5 and Devuan 3.0 #238/September 2020 Speed Up Your System Your Linux experience goes much more smoothly if your…

We are always looking for good articles on Linux and the tools of the Linux environment. Although we will consider any topic, the following themes are of special interest: • System administration• Useful tips and tools• Security, both news and techniques• Product reviews, especially from real-world experience• Community news and projects If you have an idea, send a proposal with an outline, an estimate of the length, a description of your background, and contact information to edit@linux-magazine.com. The technical level of the article should be consistent with what you normally read in Linux Magazine. Remember that Linux Magazine is read in many countries, and your article may be translated into one of our sister publications. Therefore, it is best to avoid using slang and idioms that might not be understood…

Jon “maddog” Hall is an author, educator, computer scientist, and free software pioneer who has been a passionate advocate for Linux since 1994 when he first met Linus Torvalds and facilitated the port of Linux to a 64-bit system. He serves as president of Linux International®. Teaching Three Times All the upheaval around COVID-19 has at least one bright spot. Many conferences have moved to being “virtual only.” While the time and effort to create and promote these conferences can still be considerable, the monetary cost is dramatically reduced, so many of them have shifted from charging for admission to a sponsorship-only model. Therefore they are offered to attendees for the “price” of accessing them over the Internet. And, the organizers record the talks so people can view them later.…

Sparkling gems and new releases from the world of Free and Open Source Software Ebook editor Sigil Online book sellers and the self-publishing revolution have changed the publishing landscape for book authors. No longer are the keys to the printing press held by the few, and success is no longer limited to those with a publishing agent and book deal. In the 21st century, anyone can publish anything. There are obvious negatives, too; there’s a lot of rubbish out there, and the ratio between poverty and success is similar to that of winning the lottery. But it is possible, and success can be measured in many different ways. There are a few things you need if you’re going to publish your own book, apart from the talent, drive, and commitment…

Anyone can strum three chords. What I really admire about musicians is their ability to sing all of their often lengthy lyrics by heart. Having said this, there are some hilarious examples of the massive divide between what the artists originally sang and what the fans thought they heard. Take the Eurythmics song “Sweet Dreams,” for example; although some people’s sweet dreams may be made of cheese, it’s not what Annie Lennox and Dave Stewart had in mind. Or, keeping to a foodie theme, there’s the hilarious mishearing of the 1980s Starship classic “We built this city on sausage rolls,” – the city in question being San Francisco, my own place of residence, which of course is more famous for rock and roll. As a portable tool to help budding…

Christmas fun for makers Maker Christmas Christmas fun for makers Maker Christmas My idea of building a music box of my own design was born from these frustrations. In terms of the electronics, you do not need many components. The following sections are intended to give you some ideas for your own projects; the parts used in this example can easily be replaced by whatever delving into the depths of your lumber box reveals. The only important elements in this project are light, motion, and music. Controls To control the project, I used a Trinket M0 microcontroller [1] by Adafruit (Figure 1), which runs CircuitPython, a minimalist Python that supports a wide range of peripherals with its many libraries. The price of the controller is in the same range as…

Shared hosting remains the go to choice for many first-time webmasters. The shared-hosting model, which allows several websites to share the same centrally managed server, lets the customer focus on web matters without getting involved with the details of the underlying OS. But the simplicity of the shared hosting environment also leads to some complications. For instance, although many shared hosts do allow users to connect to the shared server over SSH, hosting vendors typically don’t provide root access for shared-hosting customers. From a backup perspective, this lack of root access makes life a little difficult. Although there is a vibrant market of third-party vendors and managed service providers (MSPs) offering various types of cloud-to-cloud backup and data extraction solutions, many tools are proprietary and are not designed to allow…

AsciiDoc [1] is a publication and documentation system, as well as a markup and formatting language. The simple syntax and clear-cut markup make source code edited with AsciiDoc easy to read directly. However, those familiar with AsciiDoc may be interested in the additional features available with Asciidoctor. While Asciidoctor is designed for compatibility with AsciiDoc, there are points at which it differs from the original, including greater speed and a number of useful features. New Capabilities AsciiDoc’s first versions date back to 2002. Today the packages are part of the standard feature set in many distributions and can be imported from their repositories. Besides HTML and XHTML, AsciiDoc supports the DocBook output format, which is useful as source material for generating specially formatted HTML, PDF, EPUB, DVI, LaTeX, roff, and…

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-magazine.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 events@linux-magazine.com. NOTICE Be sure to check the event website before booking any travel, as many events are being canceled or converted to virtual events due to the effects of COVID-19. DrupalCon Europe Date: December 8-11, 2020 Location: Virtual Event Website: https://events.drupal.org/ DrupalCon unites experts from around the globe who create ambitious digital experiences. Session tracks include Javascript, Front End, DevOps, Content Strategy, Site Building, PHP, and more. You'll leave…