Linux FormatMarch 2022的目錄

Jonni Bidwell The modern web has too many moving parts. Look how many domains/scripts any major website connects to, then all the cookies and objects that are dropped into local storage. These tracks are hard to cover, so I’ve been looking at Project Gemini (https://gemini.circumlunar.space) a lighter, simpler hypertextual domain. Nick Peers My main use for a VPN is as a client (Cyberghost) for connecting to insecure public Wi-Fi networks on my phone or tablet. I have successfully set up a VPN server too using my QNAP for remote-dialling into my network. I wish I could remember how I did it, though, because it’s a complicated setup… Les Pounder I receive all my emails and files via a specially trained team of pigeons that fly in random flight plans around…

TikTok is a hugely popular video-sharing service and has recently released a new desktop application, known as Live Studio. However, shortly after the launch the company was accused of using code from OBS Studio without adhering to the GNU General Public License (GPL) version 2 licence that OBS, an open source program for streaming, uses when making its code available to use. Following TikTok’s launch of Live Studio, an incendiary tweet was posted on Twitter by @Naackers (see https://bit.ly/lxf286tweet). They claimed that the new program was “a fork of @OBSProject,” and accused TikTok of stealing from OBS, which is an open source project whose source code is available under the GPL V2 licence. While TikTok would have been free to use the code, it would also need to publish the…

Managing Linux systems is largely about solving problems. It’s not unusual to be trying to solve problems that are new to us – after all, if they’re familiar then we probably know how to solve them already. What helps in solving operational Linux problems is a broad understanding of technology, often extending beyond just Linux. That makes it possible for us to form a hypothesis about the best approach to solve the current problem. However, there’s a danger in taking this approach. The steps we suspect might help us reach a solution may themselves require some research, and it’s surprisingly easy to become bogged down working on something that’s only a step to a possible solution, rather than the actual solution to the original problem. There’s a name for this:…

Ahnasty form of ransomware known as both SFile and Escal has been ported to Linux, and is now able to encrypt files on the open source operating system, according to Chinese security firm Rising (read the report using a translator at https://bit.ly/lxf286rising). When the ransomware first emerged in early 2020 it only targeted Windows systems, and it has been used in attacks against businesses and governments, encrypting files and asking victims to contact the attackers to pay a ransom to decrypt the files. Unfortunately, as well as being ported to Linux, The Record reports (https://bit.ly/lxf286record) that it’s also been ‘improved’ and can now target files based on dates and times, enabling it to encrypt more recent files that may be of more importance to victims. Thankfully, attacks using SFile ransomware…

I saw a recent blog post from Ariadne Conill discussing the Free Software Foundation’s policy toward proprietary firmware, which resonated with me. Ariadne states that the RYF (“Respects Your Freedom”) certification demonstrates how “the FSF’s relationship with firmware is harmful to free software users”. She argues that a policy against shipping proprietary firmware is self-defeating for many projects. The reason this resonated for me dates back several decades. I first met folks involved in the FSF back in the mid-1990s, at various Linux User Group meetings in the UK. At the time I was a free software fanatic. I didn’t have a pragmatic bone in my body, but even I couldn’t understand the positions being stated. Computers, whether laptops, phones or servers, all rely on embedded devices that perform functions…

Q Synchronised sounds I have a music collection that’s stored on both local and external drives. I have just sorted through all the duplicates with fdupes. Now my local collection is only two-thirds of my external collection. I could delete the external copy and re-copy everything from local to external again. This would take hours, but at least it would be done afterwards. I’m looking for a more sophisticated approach that builds on the fact that every file stored at local is also stored on external. On external the files are just not sorted right and lots of duplicates are present. Because I have two more collections to sort through, it would be nice to have a better solution then having to copy everything over multiple times. Joe Doyle A…

Originally released as Early Access (Steam’s preview/crowd-funding system) back in September 2016, Oxygen Not Included has been in constant development and improvement. Linux support was added back in November 2017 and the title was granted a full Steam release in July 2019. Between 2016 and 2022 there have been a host of free content releases and endless bug fixes, while at the end of 2021 the first paidfor DLC – Spaced Out – was released for £10.29 that enables you to expand to new colonies of fresh planetoids. Customise new modular rockets to your liking, then explore the expanse of space with the newly overhauled Starmap. Huge expansions to the Research Tree provide new mid-game Rocketry options, giving your Duplicants an edge in the asteroid space-race.…

Atom and Visual Studio Code have an advantage when it comes to user interface configurability because they’re based on Electron rather than using one of the standard GUI toolkits, and themes affect the GUI and text area. The Atom developers welcome users hacking the configuration files: chapter three of the online manual is entitled Hacking Atom. Visual Studio Code is so endowed with configuration options that you may have to search the web for answers when trying to figure out how to change something. Balancing this out a bit, its masses of configuration options are searchable, a feature that we think should be more widespread in the world of Linux applications. Kate is a more traditional-looking application. Unlike Visual Studio Code and Atom, it may not be possible to customise…

Consumer VPNs (virtual private networks) are big business. Indeed, if all the sponsored product placement and affiliate linking is anything to go by, then just a few bucks a month will bring you great security, privacy and other nebulous benefits, while at the same time making you magically appear as though you’re in a country of your choosing. What those implorations to sign up don’t tell you is that while you’re holidaying, safely, in this faraway IP block, your traffic (albeit partly encrypted) is all visible to the VPN provider. It might care more about your monthly subscription payment than what you’re using its service for. And it might well implement a ‘no-log’ policy, which would save space and money. But they effectively have the same insight into customers’ traffic…

Ten years ago, I was sat at my computer waiting to purchase a Raspberry Pi. I got my Raspberry Pi, but alas I had to wait weeks for delivery. Between buying and receiving my Pi I went to the first Raspberry Jam in the world. The organiser, Alan O’Donohoe, had gathered together Raspberry Pi fans to create an evening of Pi. We played Quake 3 and ran a thin client to a Windows server. When the Raspberry Pi was still hard to buy, Pete Lomas came to Oggcamp 2012 with a car-boot full! The Raspberry Pi has evolved. It’s now a viable desktop computer that’s sold over 40 million units. The community has grown along with the Pi, and the children who were there at the start are now adults,…

A new Raspberry Pi OS release is something to celebrate, because free new things are great, right? Well yes and no in the case of the latest Raspberry Pi OS, which is based on Debian 11 Bullseye. We’ll start with the good news. Overall the new Raspberry Pi OS feels faster, slicker and more “desktop” than its predecessors thanks to a new window manager, Mutter. However, this introduces some fragmentation to the boards. Mutter only works with Pis fitted with 2GB of RAM or more, so that’s the Raspberry Pi 4 and the Compute Module 4. If you don’t meet the specs then it’ll default to the older Openbox window manager. Bullseye also brings an easier update tool, hidden in plain sight in the menu bar. This GUI updater checks…

Part One Don’t miss next issue – subscribe on page 14! One of the great things about Linux, and open source in general, is the ability to leverage the work of others in order to make something better. Or at least better for you. Today’s Linux distributions do exactly that, assembling individual upstream projects such as the Linux kernel, GNU utilities and applications into a cohesive operating system that’s easy to install and use. Of course, you can always customise a Linux distro by adding packages, features and applications as desired. But the Linux From Scratch (www.linuxfromscratch.org) project (hereafter also written as LFS) takes a different tact. LFS enables you to build a Linux distribution from the ground up. Sound fun? Well it is, but it’s also a fair amount…

Credit: www.ventoy.net Before describing what Ventoy is, let’s discuss a couple of scenarios. Scenario one: after performing an upgrade on your daily driver laptop there’s an issue with the bootloader and it won’t boot into your favourite Linux distro. What now commences is a desperate scrabble to find the USB stick that contains recovery tools. When that fails, one has to decide which memory stick to wipe to then install said recovery tools. Scenario two: distro-hoppers are likely to have a fair number of USB sticks that contain different distributions. When a new version is released, a USB stick needs to be wiped to install the new version. Ventoy changes the way USB devices are used to boot into different operating systems. When written to a USB stick, the device…

Hardware keys aren’t a magic bullet. Badly implemented systems or flawed encryption schemes (Governmentmandated backdoors? – Ed) all offer ways that in the long term are going to be exploited by bad actors. One example from back around 2012 was the RSA SecurID 800 widely used by US government agencies. Researchers refined a 2002 method that reduced the time to retrieve the cryptographic keys used in the RSA signature to just 13 minutes. This also affected similar devices at the time to a lesser degree. The method used a command from the PKCS#11 API in a million message attack to leak a 1,024-bit key in as few as 9,400 calls, which the researchers claimed was low enough to be practical. RSA disputed the claim, admitting the RSA SecurID800 at the…

Recipes are copyrighted unless explicitly stated. This means that someone owns the rights to the layout, the formulation of ingredients, and the individual steps of the method used to make the dish. Obviously, the authors intend for you to use the recipe, but only as a way of helping you prepare the perfect pastry. It’s unlikely that amateur chefs want you to steal and republish their hard work. Obviously, cooking, as a field is based on borrowing and sharing ideas, and a factual list of ingredients and basic steps is unlikely to get you into trouble. Introductions might though, as could turns of phrase that are anything beyond ‘just the facts’. A group of recipes together can also form the basics of a copyright infringement claim, so make sure that…

We’ve discussed the early days of the web and how Perl became a de facto scripting tool. Later, in a time when people thought it was a good idea to give version numbers to general concepts, this would usher in the “Web 2.0” era. This mainly refers to the ease with which regular web users could create and publish their own content, and interact with others. This chapter was powered by web frameworks, and so several languages came up with their own, some of which are still around today. PHP has Laravel, Python has Django, Ruby has Ruby on Rails, C# has C#.net (apparently), and let’s not even get started on myriad JavaScript ones. One you might not recognise, though, is Perl Dancer. It’s designed to be lightweight and intuitive,…

Sometimes we need to have a deeper knowledge of executables and shared libraries in Linux to better understand how various programs work. Linux distributions make heavy use of shared objects, which normally reside under /usr/lib64 on an average x86_64 system. Here you can find plenty of *.so files, which people often call ‘libraries’ for brevity. Together with binary executables under /usr/bin, those shared *.so files have numerous inner dependencies or links between each other. A traditional way to examine such links is to use the $ ldd command, but its output can still be difficult to break down and make sense of. That’s why we advise using Libtree, an enhanced implementation of ldd that outputs all links in the form of a tree. Give it a try with any executable…

I have no idea what you get up to online and you know what, I don’t want to know. You know who does? Pretty much every government and corporation in the world. This wasn’t supposed to be a paranoia-fuelled introduction and it isn’t. The hard facts are Google, Facebook, Twitter et al. openly do their utmost to track your online (and real world) movements to the nth degree. Turning to nation states, China openly monitors and restricts its own citizens to a drastic level (so imagine what it’s happy to do with you) and it’s well documented the Five+ Eyes intelligence alliance (USA, UK, Canada, Australia, New Zealand and other buddies) monitor each other’s citizens and then share the data back, so no pesky local laws manage to get in…

Linux PCs running on Intel’s new Alder Lake generation of CPUs should be in line for a performance boost, with the company patching its Linux drivers to support its Thread Director technology. Intel’s 12th generation processors are hybrid CPUs, comprising performance and efficiency cores. In Windows 11, which already has support for Thread Director, the operating system could switch between cores depending on what kind of task was being performed. Using the performance cores would offer better results when doing intensive tasks, while switching to efficiency cores when idle or performing light tasks could prolong battery lives and reduce temperatures. As Phoronix reports (https://bit.ly/lxf286phoronix), the Linux kernel relies on ITMT/Turbo Boost Max 3.0 driver code to switch between cores, which isn’t as adaptive at the solution in Windows 11, which…

Linus Torvalds got 2022 off to a good start by announcing Linux kernel 5.16, which he had delayed by a week due to the holidays. The new kernel includes a number of changes. Among the bigger items is a new futex_waitv() system call (syscall), which will benefit gamers who use Proton to run Windows games on Linux. Windows has an OS primitive known as WaitForMultipleObjects that can be used to block (wait) for any of several different things to happen at once. Linux doesn’t have a similar operation, instead requiring many different calls to achieve the same thing. The new kernel will potentially make Proton games faster. Linux 5.16 also introduces memory folios as a means to more effectively leverage larger memory allocations formed from many “pages”, as well as…

Linux uses kernel modules: separate pieces of driver code that are loaded by the kernel when needed to access each piece of hardware. Some of these are built into the kernel, but the majority are separate files because there’s so much hardware supported but each system only needs a few. This is great when Linux is running, but what happens when you need one of these modules to boot? This is why we have initramfs files in /boot. One of these files is a filesystem on a file that’s loaded by the kernel before it does anything else, then it has access to all the modules in the initramfs. The initramfs also contains startup routines that take care of tasks like assembling RAID arrays, unlocking encrypted filesystems and handling any…

Besides the two usual editions, for proprietary (Nvidia) and free (AMD/Intel/Nouveau) graphics drivers, Pop 21.10 introduces a ‘tech preview’ for the Raspberry Pi 4. We couldn’t but help give this a whirl, expecting from the name a few rough edges. Cosmetically it’s identical to the x86 edition, but the initial set up looked odd on our 1,440p monitor. Like the Pi edition of Ubuntu on which it’s based, Pop!_Pi suffers from lag and a lack of responsiveness. Powerful though the Pi 4 is, it seems to be no match for Gnome. Another problem is that Flatpak applications in Pop!_Shop aren’t filtered by architecture. So while it looks like you can install Slack or Steam in a single click, that is in fact impossible. ARM builds of those programs don’t exist.…

This month we’re looking at Linux text editors. Specifically, we’re looking at GUI text editors, and the ones we’ve chosen are all free and open source. We’ve decided to exclude hybrid editors that owe their underlying technology to the two mighty titans of Linux text editing: Emacs and vi. We’re also restricting our selection to what you might call ‘serious’ text editors rather than lightweight options. Two of the editors we’re looking at, Atom and Visual Studio Code, are implemented using the Electron framework. Admittedly, it’s a “high performance” (I do not think those words mean what you think they mean – Ed) framework, but they’re ultimately similar to a type of web application that’s contained within a window. It means they lack the native feel of the operating system…

How large the community around an editor is becomes an important factor in how easy it is to find out information about it. Visual Studio Code benefits in this regard from its popularity on a variety of platforms. In addition, the official documentation is top-notch. A link in the Help menu takes you to the website manual, which is comprehensive. Beyond that, the program even offers what it calls ‘walkthroughs’ that feature interactive instruction documents that open inside the editor with areas in which you can practise certain skills. It’s the most complex of the text editors that we’ve looked at, but this is balanced out by the fact that it has the best documentation and training facilities. The KDE website houses a comprehensive manual that covers all of Kate’s…

Search online for “why I need a VPN” on any and you’ll find flashy websites framing all sorts of shoddy prose on the perils of “unprotected” browsing. Such diatribe should be taken with a grain of salt. Yes, there are companies that sell your data. Yes there are brutal regimes that punish anyone caught browsing websites that go against their ideologies. Yes, Google is mostly blocked in China. And yes, a VPN might help you with this. But it’s perhaps not as essential as people think. We’re getting ahead of ourselves anyway. A VPN is an encrypted tunnel between two, generally distant, machines. There are a variety of protocols by which one can achieve this, but they all enable the client machine to access resources (web pages, VOIP services, internal…

Another of OpenSSH’s joyous treasures is that it can be used as a SOCKS proxy. This isn’t the same as a VPN; it works at the session level rather than the transport level. But it does enable traffic to be tunnelled over an encrypted connection and it does obfuscate the client IP address, which is certainly part of what a VPN does. Let’s assume you have a remote machine which you’re already in the habit of SSHing into. Then to achieve this SOCKS magic, instead of your usual incantation, add the following option: This will send traffic from port 3128 on the local machine to the proxy (you can use any available port number you’re allowed to). Also, the -D option can be activated from the internal shell we tipped…

When you connect to a VPN, as well as proxying your traffic and setting the corresponding updates to your routing table, it may also provide you with different DNS settings. On paper this was a reasonable idea. Traditional DNS requests (for example, where linuxformat.com is resolved to 172.31.5.172) are transmitted in the clear, so even if the operator of a DNS server (typically ones ISP) doesn’t know the web page a client is looking at, they at least are aware of the server it’s on. This is known as DNS leakage. You may use another DNS server (such as Cloudflare’s easy-to-remember 1.1.1.1 public offering), but again this is only viable if you trust that operator more than your ISP. ISPs may also block certain domains at the DNS level (the…

So, you say you have a high-quality, low-power, small yet powerful computer system that can integrate easily with other systems and doesn’t cost very much? Well, just you come and cosy up to my friends over here in the land of business and we might be able to put you to good use. And you say you run Linux, too? Better still! With that the Raspberry Pi Compute Module was born. Eben Upton has mentioned that almost half of all Raspberry Pi sales go into industrial applications. One well-known use is in Panasonic TVs and we imagine that’s why the Pi 4 Compute Module was created with its HDMI 2.0 4K support. But it’s finding industry applications such as the IoT gateway that comes in a DIN-rail package utilising the…

Credit: https://shop.pimoroni.com Add-on boards for the Raspberry Pi, known as HATs, expand the usefulness of the $35 single board computer. The Pi has a single 40-pin GPIO header, but with pHAT Stack from Pmoroni we can add three HATs, or five pHATs to a single Pi. In this project we’re using two older HATs from Pimoroni. The Skywriter HAT is a gesture sensor that reacts to flicks, taps and touch using a sensor which can detect your fingers in the air. We’ll use Skywriter as an input to control the 64 NeoPixels housed inside of Unicorn HAT. The LEDs will change colour at the flick of our hand. Best of all, there is no wiring to worry about. PHAT Stack connects to the Raspberry Pi GPIO via a ribbon cable.…

Going through the exercise of building LFS can prepare you to assemble your own, customised Linux OS. There are other projects that aim to accomplish this in a more point-and-click fashion, however. The projects below enable you “re-spin” the most popular standard distros, as follows: Linux Live Kit, www.linux-live.org: this project provides the ability to create a bootable ISO file from your favourite distribution, suitable for running from a CD or USB drive. The project recommends Debian, but supports other distributions as well. Ubuntu Imager, https://github.com/Distroshare/distroshare-ubuntu-imager: this command-line utility takes input from a configuration file, then assembles a custom Ubuntu-based ISO file. Image Builder: the Fedora distribution contains the Image Builder tool that enables custom OS image creation. Based on tools from the Weldr project (https://github.com/weldr), they’re available either in…

Sharing your timelines with other Timeline users is easy: just send them a copy of your file. Timeline files contain everything they need – including any images you’ve attached to events – to view your file up close. If you make it read-only before distributing it, they won’t be able to make changes without creating their own copy of the file. But what about non-Timeline users? The answer lies in the program’s File>Export menu, which reveals five different options. The first is a simple SVG graphics file, which exports the current view as a vector graphics file, which means that it’ll print properly at any size. The ‘Export to Listbox’ option brings up a dialog listing all events in chronological order. Click Copy and all items are copied to the…

It seems to be a tradition that each issue we highlight an online tool to emulate a retro computer, and we continue this with the MSX. WebMSX is a remarkable emulator that lives online at https://webmsx.org. Created by Paulo Augusto Peccin, WebMSX is simple to use: we can drag and drop disk, cartridge and tape images on to the emulator or we can load them using the handy drives located at the bottom of the emulator. We tested Metal Gear, Aliens and the Bad Apple demo with WebMSX and they all worked perfectly. The emulator is accessible via webmsx.org or you can install it to your own machine. Open a terminal and clone the git repository, like so: Inside the directory are a series of subdirectories, and inside the following…

Aswathe of interesting system monitor programs has recently become available for Linux. If the Monitor tool that we covered in LXF283 is a little too minimalist for your tastes, you’ll want to take a closer look at System Monitor Center. The program packs multiple system tools into a single-window GTK application. System Monitor Center has as many as eight sections, of which Performance and Processes cover most features that other Linux monitoring tools usually provide. Under Performance you can find sub-sections with live CPU/disk/RAM graphs, and even thermal sensors. The remaining six sections monitor user sessions, storage information, desktop startup items, Systemd services, environmental variable and detailed system information. Many sections and their views have the gear button for customising elements such as units and the amount of columns on…

Professional image editors often have a nondestructive mode, which means that whatever edits you make to an image, the original version is retained. Our latest Hotpick is Caravaggio, an image editor that performs all operations in a nondestructive mode. And there its similarities with any standard image editors ends. Caravaggio is a web service that processes images on the fly by providing a limited set of editing tools. It neither exposes any API, nor it has any local storage. Instead, Caravaggio applies all edits directly based on what’s been provided within the URL. To better understand how it works here’s the template of an URL, which blurs an image with Caravaggio: Caravaggio has a public test server at caravaggio. now.sh, but you can easily host your own Caravaggio instance after…

Object orientated programming techniques have been used in this project. The worldmanager.py script file contains a collection of classes used to create and construct the view of the 3D world. These classes include the WorldManager and Camera class. The WorldManager class consists of a class constructor and a method called draw() which is used to render the 3D world. Each class in Object Orientated Programming employs a constructor that’s used to initialise values and perform initial operations when and instance of that class is created or called. For example, the constructor in the WorldManager class is used to load images both for the objects that can be shown when the program is running and also the texture images for the wall. The constructor of the Camera class is used to…

According to research from Stack Overflow, only 25 per cent of developers are happy in their role and not looking for a new job. Around half of all developers are open to offers, while 24 per cent are actively looking. If you manage a team, what should you do to keep the developers you have, and attract more high-quality recruits? It comes down to developer experience: how those programmers and architects find it to work every day can have a huge impact on how happy they are, and consequently more likely to remain. Making it easier to work helps existing developers be more productive, while more than 53 per cent of developers state that developer experience is a key element in choosing any new role. Typically, using cloud services or…

After 30 years, it looks like a.out support will finally be removed from Linux. While the once-popular file format (which was replaced by ELF in the mid-1990s) was deprecated in 2019, a patch has been proposed (https://bit.ly/lxf286patch) to remove a.out support completely from the kernel. The proposal by Borislav Petkov appears to have broad support from other upstream developers, and while it may not make the 5.17 merge window, we could see it disappearing later this year. The proposal is rather brief, saying that “deprecated a.out support with the promise to remove it a couple of releases later. That commit landed in v5.1. Now it is more than a couple of releases later, no one has complained so remove it.” As Petkov observes, since a.out was depreciated in 2019, there…

It’s been just over a year since we first announced an effort to implement a Wayland driver for Wine. Since then a lot of work has been done to improve the functionality and stability of the driver, and to provide a more upstreamable patchset. This work continues as we expand our testing and receive community feedback. The Wine Wayland driver now features full window handling (all types and states including pop-ups, arbitrary sizes and the System Tray), full-screen handling for all different resolutions, accelerated graphics (OpenGL and Vulkan, including DirectX via WineD3D/DXVK), HiDPI support, relative mouse motion input support for games and CAD, rich keymaps and more. A currently open issue is related to cross-process, which is particularly relevant for Chromium/CEF based applications, like some game stores applications. For now,…

With the introduction of memory folios into Linux 5.16, much ongoing development has involved conversion of existing subsystems to use folios. A recent example is that of an overhaul to the venerable “struct page” used to track memory in units known as pages. A number of pieces were moved out into a new “struct slab” used by the low-level memory allocators. And Matthew Wilcox (the folio author) is far from done: he’s working on a set of patches for the “GUP” (Get User Pages) code to adapt that next. Jason A Donenfeld posted a patch titled Remove remaining users of SHA-1 which aims to clean up legacy users of the (now insecure) SHA-1 algorithm. In this case, it’s replaced with BLAKE2s, which is based on the ChaCha stream cipher that’s…

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We put each of the text editors through their paces by opening up and editing source code files in the C, Dart and C# programming languages. We also opened a variety of configuration and log files of the type that you’re likely to encounter on a typical Linux system. Some text editors are touted as ‘lightweight’, and if you had to outfit a constrained platform such as an older computer or a Raspberry Pi, then that might be worth taking into account. However, in this era of computers with fast, multicore processors, lots of RAM and SSD drives, we don’t consider that to be as important a factor as it once was. The modern, heavyweight text editors in our Roundup – Atom and Visual Studio Code – loaded slightly more…

We’ve not looked at any of the lightweight Linux editors this time around. Leafpad (http://tarot.freeshell.org/leafpad) is a good example of a simple editor that can be used to edit the odd script or configuration file. Gedit (https://wiki.gnome.org/Apps/Gedit) has followed the trend of many GNOME applications and is now highly stripped down, although it does offer syntax highlighting unlike Leafpad. Unfortunately, it was also slow to open the huge syslog file that we tested with. Brackets (https://brackets.io) is a text editor aimed at web developers. We were able to install a 2019 version via Snap, but all mentions of the Linux version have now been removed from the website. Rider (www.jetbrains.com/rider) and Sublime (www.sublimetext.com) both have modern-looking interfaces and a lot of cutting-edge features for programmers, but they’re commercial software and…

VPNs are advertised as being a boost for privacy, security and anonymity. Those nouns may well apply in particular situations. But it’s hard to call a VPN an anonymous service when you have to sign up with a very un-anonymous credit card. And it’s hard to say for sure if they’re private or secure if you’re talking about a bunch of effectively centralised servers that no one can audit. Fortunately there are alternatives, and one you’ve probably heard of is Tor (formerly known as The Onion Router). Similar to a VPN, Tor proxies traffic through encrypted tunnels, obfuscating users’ IP addresses. It’s different though because no one entity owns Tor. Anyone can run a Tor node and anyone can connect to it for free, without any sign-up process. Tor connections…

Cretaceous period – 2006 Eben Upton had the idea of an easily built home-PC kit. Behold the Atmel ATmega644 system, which sat on a Veroboard with a block SRAM. The device ran at 22.1MHz and had to drive the display too, leaving blanking periods for processing. Upton later decided that a SoC capable of running a general operating system would be more useful, good lad! http://bit.ly/RaspPi2006Ed May 2011 – Proto Pi Early in 2011 David Braden of Elite fame was showing off a prototype USB device that he was calling the Raspberry Pi (http://bit.ly/EarlyPIOnBBC). Resembling a USB stick than the Pi we have today, this compact concept was dropped in favour of one that enabled the device to have more connections and the crucial GPIO pins. August 2011 – Alpha…

Skywriter is a fun introduction to gesture inputs, but there are many more sensors we can use for contactless inputs. The most basic is a PIR (Passive Infra Red) sensor. Commonly used to detect movement in alarm systems, these sensors are digital and send a pulse of voltage when movement is detected. They’re an excellent sensor for use with children because it introduces movement and excitement. The next sensor is an ultrasonic distance sensor (HC-SR04) that’s used in parking sensors to determine the cars’ distance to a wall. Raspberry Pi robotics teams use them to create autonomous robots. The HC-SR04+ and HC-SR04P are best for the Pi because they’re 3.3 and 5V tolerant, whereas the HC-SR04 is only 5V. RCWL-0516 doppler radar sensors can detect movement through objects, and can…

While LFS shows you how to build a Linux-based OS from source code, it’s important to distinguish it from true source-based distribution. Examples of these systems include Gentoo Linux, NixOS and CRUX. They all share some of the advantages of compiling from source, such as the ability to optimise for the specific hardware of the machine on which they’re installed. However, when comparing LFS to these systems, they provide a number of functions to make users’ lives significantly easier, including: Automated build systems that will download source packages and build them with a single command. Dependency resolution, enabling both the application and all its prerequisites to be downloaded and built. Modern distribution features such as hardware detection. Wider software selection, which is updated more regularly. Source-based distributions provide another option…

Writing a feature such as this takes time and most of that is research. The biggest resource that we referenced is www.msx.org. This resource is a one-stop-shop for MSX fans. We found excellent MSX BASIC command references, along with examples to illustrate their output. The site also houses archives stuffed full of general and specific information on most MSX models. We found information on how to access floppy disks, general commands and learned how to access MSX formatted floppies using a Linux PC. The community side of MSX is well represented via forums and a directory of demoscene (www.msx.org/wiki/Category:SceneDemos) and disk magazines (www.msx.org/wiki/Category:Disk_Magazines). For the demoscene we went to our old favourite pouet.net, specifically the MSX section (www.pouet.net/prodlist.php?platform%5B%5D=MSX). There we found pages of great demos to illustrate all models of…

ISSUE 285 February 2022 Product code: LXFDB0285 In the magazine Stay one step ahead of the nefarious perpetrators of ransomware with our in-depth feature. We bring you tutorials on rock music effects, offline password management and creating a virtual network lab. Discover how to set up a temperature display for your Raspberry Pi and build web services with Go and the Gin framework. We also put five of the best GUI-based backup tools through their paces. ISSUE 284 January 2021 Product code: LXFDB0284 In the magazine Discover how to turn your Raspberry Pi into an all-singing, all-dancing media hub. We put a spotlight on video conversion tools, take you on a tour of Stacer, the one-stop system management tool, and emulate the Oric-1 (thankfully without that keyboard). Discover how to…

Some websites will offer to allow the user to use one-time SMS authentication codes. They provide some protection, but not a huge amount. SMS codes have a fatal flaw: attackers who are sufficiently motivated and resourced can take over a mobile phone number with a technique called “SIM swapping” and any SMS code will be captured by them to use for nefarious purposes. This requires either very good social engineering or having a bad actor at the network provider that can take over the identity and move it to the baddies. This isn’t a theoretical situation. It’s a well-known attack that’s been used by a number of bad actors to steal high-value items from third parties, usually crypto currency related – BitCoin and similar. It’s even been used to take…

There’s no way of predicting which recipe sites or even recipe pages come with properly formatted recipe schema JSON. Even sites that attempt to follow the guidelines fail in some way or other, and there’s no guarantee that they’ll continue to do so. While we spent most of last year, automatically sucking down ingredients from the Slimming World site, for instance, we’re no longer able to do so. Something has changed in the site layout, which leaves us only with an image and a short descriptive passage. With recipes from BBC Good Food, you’ll need to separate the instructions into individual steps and then adjust the cooking time manually. It correctly identifies and itemises all of the ingredients in all three recipe managers. For recipes from Asda Good Living, you…

The first Perl conference was held by O’Reilly in 1997 and brought together businesses and contributors from across the globe. Larry Wall’s keynote urged for greater cooperation between enterprises and the free software community. So successful was this convention that by 1999 it had grown into a sort of World Fair for Open Source. But it wasn’t called that, it was called OSCON. In 1991 O’Reilly had published Wall and Randal L. Schwartz’s Programming Perl (aka The Camel Book), which acted as the definitive manual for Perl 4, further popularising the language. And from 1995 to 2002 Wall was employed by O’Reilly to write more Perl books and spread Perl Wisdom. Smaller, grassroot initiatives were key to the Perl community. In 1997, the first chapter of Perl Mongers was set…

This author used to have a custom-made backup system that would update an extra copy of the $HOME directory on an external drive each night. That was a simple combo of Cron and a custom-tailoured Bash script, which contained the notification solution: the script collected all details in a log and then sent it via Postfix to a Gmail account. That was fully functional, rock-solid, but there was always the feeling that there could be a more elegant solution of being notified of a backup attempt. If you agree then take a look at Ntfy, a great way of pushing custom messages right to your Android phone (iOS support isn’t here yet, but it’s being worked on). It’s blazingly fast, easy to set up and totally free. You’ll need to…

Python has a powerful mathematics library that has a range of uses. In regards to the project featured in this tutorial, the trigonometric mathematical functions have been used such math.cos and math.sin and also math.abs. The Python math library can be included by writing this code in a Python script: The functions from the maths library that have been used in this project are: math.cos(x): the cosine of x radians math.sin(x): the sine of x radians math.abs(n): the absolute value of the specified number In the Python script file, main.py, two of the three trigonometric mathematical functions have been used when the player turns either left or right in the game environment. See this code example from the project to learn how this has been achieved: In the Python script…