Innholdsfortegnelse for February 2018 i Linux Format

This issue we asked our experts: Because we’re building a Linux PC this month, we wondered what’s running inside your rig and what tricks have you added to make it extra special? Jonni Bidwell I did have two power-hungry graphics cards in my rig, but after my newfound passion for mining ethereum, core reactor temperature was reaching critical. One PCIe riser later and that card is now mounted outside the case, warming my toes rather than my CPU. Nate Drake While escaping from my cubicle at Apple last year, I was able to snatch up a Mac Mini server. I maxed the RAM and then fuelled my paranoia by installing a Seagate SED (Self Encrypting Drive). I’ve plastered a decal of Tux eating the apple on the casing for good…

“The past months have been crazily busy as we’ve tried to get people’s documents back under their own control with Collabora Online. Having brought our LibreOffice-based basic editor to the browser, we’ve been making it easy for people to play with it by partnering it with all sorts of open source file syncing solutions from OwnCloud and Nextcloud to Pydio, Seafile and others. We’ve seen two million docker image downloads of CODE too, and now feature as an easy-to-install Univention app. We’ve also been working on the next version: 3.0 which ships the infrastructure for bringing the first, full-feature LibreOffice dialogs, familiar from the PC version, to be used in the browser. One of the traditional challenges of a browser-based office suite has been trading collaboration against a limited feature-set.…

While Intel has been getting flak for the vulnerabilities found in its Management Engine (see LXF232 and LXF225) , AMD has also come under scrutiny for its similar Platform Security Processor (PSP), with critics of the closed-source network-capable co-processor claiming it could be used as a backdoor for malicious users. AMD has resisted calls for it to open source the PSP, but it seems to be listening to its critics. A new AGESA update for Ryzen-based systems enables the PSP to be disabled through the UEFI/BIOS. The option to disable the PSP was spotted by a user on Reddit (http://bit.ly/reddit-amd), and while it’s up to the motherboard manufacturers to release updates for their products, many people are now commending AMD for listening to its customers who expressed concern over the…

Hull Raspberry Jam Read how Jon Witts stepped up to the jam plate… The first Hull Raspberry Jam was held in November 2014 by Alan O’Donohoe, but there seemed no one willing to maintain the momentum. Fast forward to Easter 2016, when Jon Witts got chatting with Claire Garside (who runs the Leeds Raspberry Jam events) on Twitter about a short video of a robot he’d made with his daughters over the holidays. One thing led to another and Jon relaunched Hull Raspberry Jam in April 2016. Initially, the Jams were run in a school hall and things went well. Soon Jon had built up a community around the Jams, with people coming along to share, learn and enjoy what could be done with the Raspberry Pi. The Jams have…

Our self-imposed limitations of only working with open-source software and using distroneutral tools meant that some popular tools weren’t included in this Roundup. If you’re running Ubuntu, you can try your hands at Pasaffe. The project as of now isn’t officially supported by any other distro. Then there’s the desktop-centric keyrings such as Keyringon Gnome and Kwallet on KDE, which can also be used to store passwords. Another popular tool is Universal Password Manager, but its installation is far more involved than the ones we’ve covered in this Roundup. If you’re happy working with the command line, you can also try Pass. The robust command-line tool also boasts of several graphical front ends such as QTPass. It stores all passwords in their own separate GPG-encrypted file. If you’d rather work…

Before you begin, one thing that you should be aware of is the dangers of static electricity. This can build up on your body, particularly if you wear rubber-soled shoes or are walking on nylon or woollen carpets, which prevent all that charge from grounding. When you then come into contact with a conductive object, such as that RAM you just bought, some of this charge will discharge, which stands a good chance of sending said RAM to silicon heaven. All statically sensitive components are vulnerable to this, but you can vastly reduce the risk of administering electrostatic death to them by grounding yourself (by touching a heating pipe, the sink, or any other conductive object) before you start work, and periodically thereafter as you construct your PC. If you’re…

We’ve seen that btrfs can be used without conventional partitioning at the device level, but it can also provide it’s own data-level divisions in the form of subvolumes. On the one hand, these behave like directories, but since they can also impose quotas and can be mounted outside of the main volume, the partition metaphor works too. The main filesystem is a subvolume too, called the top-level subvolume. Among the many exciting features of btrfs are Snapshots. As the name suggests, these are a copy of the filesystem at a given in time. As the name doesn’t suggest, they are just a special kind of subvolume, one that’s a copy of some part (possibly all) of the parent filesystem. Thanks to the miracle of Copy on Write (CoW), the first…

Ann Mwangi is a software developer at ThoughtWorks, a software consultancy with offices all over the planet. Her computing journey has taken her from her native Kenya to Uganda, India and finally Australia. Ann has mentored for Rails Girls and generally is interested in getting young people into technology. She was at the O’Reilly Software Architecture conference, held in London in October 2017, where she was good enough to spare some time for a conversation with our Technical editor (who otherwise would have spent that time eating too many delicious treats and drinking tea from the generous snack area). Linux Format: How did you get into coding and software engineering? Ann Mwangi: I’m not one of those people who started coding at a very young age. I didn’t touch a…

The Calamares developers insist the installer’s design makes it easy to adapt as per the requirements of a distro. Kevin agrees: “I found the Calamares installer to be portable and easy to adapt. I made the port to Fedora (and Fedora Remixes such as Kannolo) at a time very early in Calamares development, where only a handful of distros were supported. As a result, I had to make some small adaptations that also benefitted other distributions later on. But it was all fairly straightforward.” He credits the ease of use to the project’s documentation: “I found the documentation available at the time already sufficient, keeping in mind that I’m not afraid of looking at source code or just trying something out and then debugging the error message. But the documentation…

Our expert Nick Peers has been running a Pi Zero-powered music player for the best part of two years now. It’s evolved from Pi MusicBox through Mopidy to Volumio via Rasplex. Has he missed anything out? We’re going to transform your Raspberry Pi into a music player with Volumio, a distro that has just one job: playing and streaming music. It’s relatively easy to set up, is designed for headless use and provides a user-friendly interface through your web browser for managing your music. This UI is replicated on the official Volumio apps for iOS and Android, so you can run everything from your mobile, too. It costs 99p on each platform, but you can access Volumio through your mobile browser, or try a MPD-capable app such as MPDroidfor Android…

Our expert Bobby Moss develops cloud microservices for a global IT consultancy and its clients. In his spare time he works on free software projects and tinkers with old hardware. Just a couple of months ago in LXF231 we covered the finer points of using LibreOffice Calc to sort, filter and lay out your raw data and calculations in spreadsheets that you can generate reports from. For values that can be nicely laid out in a simple table there’s no better way of extracting meaningful information from your data. However, there are limitations to that approach. For example, you might be able to fill out a table containing income and expenditure and generate a graph from it, but what happens if the laptop that you bought last year stops working…

Manually adding data and index numbers to your tables can get tiresome for hundreds of entries across dozens of tables. Thankfully for data entry you can create custom input forms that hide auto-numbering indexes, so you can focus on adding stuff like the title of a book and its author. To create one, head to the Forms tab and click “Use Wizard to Create Form...”. From here you can select all fields from the Books table apart from BookID, check the Add subform box and then add every single field in the Authors table. In the fourth step you should link the AuthorID field between the two tables, then select how to lay them out. Leave the remaining steps as their default values. After you click Finish press the arrows…

Changing the appearance of windows won’t affect the appearance of system icons and your mouse cursor. Fortunately, the Gnome Look website (www.gnome-look.org) has a huge number to choose from. You can install new icons and cursors in much the same way as for application themes. First open your home folder, right-click anywhere inside the window and choose to create a New Folder named .icons. Despite the name, both icon and cursor sets are stored here. Next, download your chosen icon and/or cursor pack and extract it to the new folder that you just created. Use Ctrl+H to view the hidden .icons folder if you can’t see it. Close and relaunch the Gnome Tweaks Tool if necessary, then go to Appearance. Your new icon theme and cursor will appear in the…

Backups are essential if and when you decide to edit the configuration files. It might not seem like a big deal if you change it and then check that it works with some applications. But in the case of the compton.conf file, what if you made some changes to it – only to discover three months down the line (practically an eternity) that your changes either slowed the performance of an OpenGL window application or caused screen tearing with another application? Or what if it wasn’t the changes you made to compton.conf, but the changes you made to your window managers .conf file instead? You can see how failure to have backups of configuration files can turn into a long ordeal of troubleshooting and trial and error as you attempt…

SSH is great, but it’s only part of a story. More often than not, you deal with local processes. How do you cope with them in Python? Of course, you can use what the “subprocess” provides. This is an option, yet it makes your code lengthy and less readable, compared to what you have in a shell. Or you can mix-match Python and shell scripts, leaving each language a niche it’s best suited to. The best of both worlds is psh, a Python library (https://pypi.python.org/pypi/psh) that makes Python feel like a shell when you work with external commands: The _ok_statuses is here so that psh doesn’t throw an exception when sort complains about head closing its file descriptors and exiting upon receiving the first three lines. psh leverages Python magic…

Before you start porting your applications to x86, you may want to check if you have the libhoudini proprietary translation layer available on your device. The Remix OS project (derived from android_x86) uses these libraries to make it possible to run Android on your regular PC. In fact, this makes almost all regular applications in the Play Store work directly from the Play Store application when running on a regular PC. If all you want to do is revive some old hardware, this is an option worth considering. The only problem is if you need high performance for encryption or similar tasks, since the translation layer slows down execution. Tests with SQLCiphershowed that the execution time was three times longer for the same operations, compared to a native environment. This…

Functional programming has become popular in the past few years. You use it to describe what you want to do, such as applying an operation to all the elements of an array, instead of describing how to get what you want, like creating a ‘for’ loop to visit all the elements of an array. The biggest advantage of the functional programming paradigm is that you’ll learn a new way of thinking and solving problems, and it will make your code smaller and more concise. Functional programming is suited for concurrency mainly because the compiler takes care of most operations that require the use of a state variable. So you can reuse your functions and modules because you know that they don’t have side-effects as is the case with object oriented…

I’ve always built my own PCs. Perhaps it’s the maker in me, but why pay someone else to have all the fun, when I can do as good a job myself? The sad truth is – while I’ve built other systems – my main home system has remained more or less the same Intel Sandybridge Core i5 2500K from back in 2011, and why not? With 16GB of memory it’s remained more than fast enough. A new graphics card here, an updated motherboard there and it’s stayed competitive for my needs. Six years on and it finally looks like there’s a range of affordable upgrade options from both Intel and AMD – six cores, multiple threads, lower-power use, better hardware acceleration, faster interfaces – that make an upgrade really desirable.…

Nature abhors a vacuum, especially if there’s an open source alternative, and Patreon’s recent travails have shown this. The popular platform that enables people to donate money to content creators recently tried to introduce new fees that would add 35 cents to each pledge. This mean for people pledging $1, the most popular amount, they would now be paying $1.35, and if they were supporting a number of creators those extra costs could soon mount up. This change caused an outcry among supports and creators, who worried that the extra fees could result in less donations. Thankfully, there were alternatives, with free and open source platforms such as Liberapay (https://liberapay.com) and BountySource (https://salt.bountysource.com) gaining more attention from disgruntled Patreon users, with many creators suggesting their donors use Liberapay instead. Patreon…

Mozilla has recently announced the initial release of its Automatic Speech Recognition engine, based on work carried out by the Machine Learning team. The DeepSpeech (https://github.com/mozilla/DeepSpeech) engine is modelled on Deep Speech papers published by Baidu (www.baidu.com), a Chinese web services company that’s one of the leaders in AI development, and details a trainable multi-layered deep neural network. The ambitious project initially had a goal of hitting a ‘word error rate’ of less than 10 per cent. However, Mozilla says the engine’s word error rate on LibriSpeech’s test-clean set is now 6.5 per cent, clearly beating this goal, and achieving close to human-level performance (which occurs at around 5.8 per cent, according to the Deep Speech 2 paper). The company also revealed its Project Common Voice, a publicly available voice…

WINE 3.0 RC1 The release candidate for the popular program that enables you to run Windows applications in Linux has been released, marking the beginning of the code freeze period in anticipation for the final release. In the latest version, Direct3D 11 is enabled by default for AMD and Intel graphics cards, there’s registry export support with the reg.exe tool, plenty of bug fixes and much more. Check out the release announcement at www.winehq.org/news/2017120801 for more information on what’s new. MX LINUX 17 This lightweight disto is based on Debian 9.3 with the Xfce 4.12 desktop environment, and the latest version comes with the 4.13 kernel, including a 32-bit version, new drivers and updated packages. These include Firefox 57.0.2, VLC 2.7, Clementine 1.3.1, Thunderbird 52.5, LibreOffice 5.4.1 and LuckyBackup 0.4.9.…

Escape nothing Escaping Windows is always a great idea. I hope that your article persuades more people to take the Linux path. As usual though, there’s more to Linux and UNIX than meets the eye and the Escape Windows article is missing an important option where you say that there are three ways to run two or more command. A fourth can be added, namely using a single ampersand between commands. Linux, as with the original UNIX, is a multi-tasking operating system and so you can easily run multiple commands concurrently. Building on your ‘cp’ example: cp source_1 destination_2 & cp source_2 destination_2 This would fire off the first cp and run it in the background, then immediately run the second cp at the same time, but in the foreground.…

For a long time, password managers were available exclusively as desktop tools. It’s only in recent years that browser-based alternatives have come to the fore. This probably explains why bitwarden, the only browser-based tool on our selection, has the most detailed documentation. Its website hosts a large number of articles: everything from getting started and creating and managing entries to the security measures available to safekeep your data are discussed in detail. The project’s blog is also an excellent resource to learn about new features. Encryptralso provides a getting started manual. It serves as a quick introduction to the tool and how to use it to create entries. KeePassXC hosts a very thorough FAQ covering various topics and introducing key features such as adding words to the passphrase generator. There’s…

Desktop case Cases come in all shapes and sizes. The mini ITX form factor is popular, and is ideal for home-theatre PCs. However, the more compact cases won’t admit a full-size ATX graphics card, optical drives, or even 3.5-inch drives in some cases. Furthermore, one needs to consider airflow. Choosing an ITX case may restrict you to an SFX power supply, and smaller motherboards tend to lack features, with fewer PCIe slots and SATA connectors than their counterparts. But for the right price, you’ll be able to find what you need. Traditional ATX tower cases are the easiest to work with and have plenty of space for drives and lengthy graphics cards (high-end ones can get close to 300mm, so be sure to check your measurements). Depending on your taste,…

5 Memory Study the manual to see which slots to use: this is most pertinent for dual-channel configurations. Note that memory is probably the most statically sensitive thing we’ll be handling. The modules can only be installed one way, and will hopefully click into place without struggle. 6 Graphics Locate a PCIe x16 slot and remove the corresponding grills (many cards occupy two slots) from the back of the case. Larger cards can be hard to wrangle into place, and may obstruct subsequent drive installation. High/ mid-end GPUs require dedicated (six- or eight-pin) 12V power connections. 7 SATA drives Your case may provide tool-less trays to house drives, but screws are more secure. 2.5-inch drives are secured from the bottom, where as 3.5-inch drives have side mountings. Use angled SATA…

Our expert Les Pounder is a freelance maker who works with organisations such as Raspberry Pi Foundation and the micro:bit Foundation to promote maker skills. Les blogs at www.bigl.es. Quick Response codes - or QR for short - have been with us for some time now. They can be used to encode web addresses, phone numbers and even virtual business cards (Vcards). In this month’s project we shall code an application to create our own QR code that contain a website address. Perhaps more interestingly, embedded inside the QR code we shall have a colour image to create our own QR code art! Furthermore, so that anyone can make their own QR codes we shall create a simple user interface using easygui. So let’s get started! Pip pip pip Installing…

Volumio.org offers several pre-built Pi-based music players, but given the cheapest weighs in at around €92 – without a Raspberry Pi – we thought we could do better. Here’s your shopping list: From https://thepihut.com Pi Zero W £10 GPIO solderless Hammer Header £2 5V power supply £5 Delivery £2.50 From www.iqaudio.co.uk Pi-DAC Zero £12 Pi-CASE+ £12 16GB microSD card £8 Delivery £5 From www.ebay.co.uk 3m OFC twin phono to phono jacks £3.50 TOTAL: £60…

Our expert John Knight When he’s not playing video games in French, John can usually be found beating a bass drum down to a kind of smooth paste. MPlayerhas a GUI, so why on earth would you use it by command line? Simple: combining MPlayer with the terminal gives you power in ways a GUI program just can’t. So much like your mum explaining why you need to eat your vegetables (until you eventually relent!), here’s to doing things the hard way. Using MPlayerwithout any fancy tweaks or options is easy. The command with all defaults simply looks like this: $ mplayer thisisanexample.avi If you’ve not used MPlayerbefore, you need to realise that MPlayeris entirely keyboard-driven. Initially this seems odd, but there’s method to the madness: flicking through videos is…

The real point of using a database over a spreadsheet is its ability to index and retrieve your data in any way you want to present it. The way this works is the database indexes fields in particular tables and is then able to retrieve individual records according to a unique ID value that’s been assigned to each record. Primary keys are a unique value that databases use to identify one record from another. For example, it defines that two John Smiths that live in Coventry are not the same human being. Similarly, it ensures that two books with unique IDs can still be attributed to the same author (with their unique ID) thanks to an additional field called a foreign key. A foreign key will often have the same…

Our expert Nate Drake is a technology journalist specialising in cybersecurity, retro tech and making your desktop look just fabulous darling! For those you that have recently installed Ubuntu 17.10, you’ll be graced with the new-look Gnome Shell. This is the graphical part of the desktop environment. If you’re new to Linux then you may be surprised to find that the panel is at the top of the screen. There’s a menu launcher at the top left, a dock containing applications on the left and various settings icons and a clock in the top bar. Despite the Gnome project’s emphasis on simplicity, the desktop actually has a huge number of features, each of which can be fine-tuned to suit your needs. This lies at the very heart of the Linux…

1 Install Firefox Add On Select “Click here to install browser extension, and then click Allow on the pop-up notification. Finally, click Add in the pop-up marked ‘Gnome Shell integration’. The add-on will install automatically. Minimise Firefox for now. 2 Install host connector The website also requires a small program in order to offer the correct extension for your version of Gnome Shell. Click Activities at the top left of your screen and then type Terminal in the search bar at the top. Double-click the Terminal icon. Then type sudo apt-get install chrome-gnome-shell . Choose Y to confirm the installation. 3 Install Extensions Return to your browser and reload the page https://extensions.gnome.org. Run a search for your extension of choice or scroll the lists. If you find one you like,…

X, also known as X11, is a windowing system for UNIX-like operating systems such as Linux. It came out in 1984 at MIT, but since 1987 the X.Org foundation have been leading the project. X uses a client-server model, enabling the forwarding of X client applications through a secure shell. Forwarding X through a shell can be useful for remotely accessing a system where a GUI is needed and due to the nature of OpenSSH it also encrypts the data packets. X is just the very basic framework for building a graphical user interface environment, in which dedicated applications such as window managers can co-exist in. Unlike earlier display systems that existed prior to X, the X window system was specifically designed to be used across network connections, rather than…

SSH client feels like a simple beast. You invoke it, you pass it the hostname… and that’s it. At most, you supply -L command-line switch for TCP connection forwarding, or -X for X11 forwarding, and earn some brownie points. Sure, the man page lists a few other options, but why should you care? Recall the last time you spun off the ssh just to remember you forgot to add -L . You can just terminate the session and respawn it again. However, ssh provides a better way: the menu. Just type Enter then ~ during your interactive session. Nothing would change visually, but the next key you type will have a special effect. For an overview, press ? You’ll see that the dot terminates current session which comes handy when…

The best place for studying the code and being inspired is Google’s own repository on Github. There are many fascinating applications here that you can import and start learning from. Since Github is supported by default in Android Studio, getting the code is simple. Just use the built-in import sample feature, which opens from File>New>Import Sample. When you open the dialog you’re greeted with a list of applications, which are sorted into categories. The categories cover new releases, hardware support and special functions. You can also clone the project locally using git, but if you do then Android Studio will have a bit of a struggle assisting you in getting the system updated to match the demands of each sample you try. You may, for example, miss the API level…

Kotlin supports the This Keyword, which, put simply, means the current object. In other words, you’ll use this when you want to access the object you’re working with or any of its properties or methods. As a result, depending on the object you’re working with, this accesses a different variable each time. So, if an object has a property named p and you want to access it from a method of the object, you can use this.p. You have already seen this in action in hwFP.kt. Additionally, Kotlin offers the super keyword, which is used when you wish to access a method or a property of the base class of an object that was created using inheritance. This is particularly handy when you’ve overridden a method or a property of…

System tools Essentials Checkinstall Install tarballs with your package manager. Coreutils The basic utilities that should exist on every operating system. HardInfo A system benchmarking tool. Kernel Source code for the latest stable kernel release, should you need it. Memtest86+ Check for faulty memory. Plop A simple manager for booting OSes, from CD, DVD and USB. RawWrite Create boot floppy disks under MS-DOS in Windows. Smart Boot Manager An OS-agnostic manager with an easy-to-use interface. WvDial Connect with a dial-up modem. Reading matter Bookshelf Advanced Bash-Scripting Guide Go further with shell scripting. Bash Guide for Beginners Get to grips with Bash scripting. Bourne Shell Scripting Guide Get started with shell scripting. The Cathedral and the Bazaar Eric S Raymond’s classic text explaining the advantages of open development. The Debian Administrator’s…

“Linux Foundation events are often the only time that those who contribute to Linux and other critical open source projects meet in person. And a core objective has been promoting diversity and inclusiveness in open source. More diverse teams make smarter decisions, generate better business results, and create more productive open source projects. There’s always more that can be done, but some initiatives we have implemented, and encourage others to as well, include: Adopting and enforcing a clear Code of Conduct across events. Awarding scholarships to allow members of underrepresented groups to attend events for free. Free child care and nursing rooms for working parents. Offering training on how to be an inclusive speaker. Prohibiting all-male panels or keynote line-ups. Ensuring venues are wheelchair accessible and providing details on medical…

“Someone was telling me recently about a business that employs technical staff to support their Linux systems. Apparently, the Linux staff at this company are expected to use a Microsoft Windows desktop system and connect to the Linux servers using PuTTY. What are the management of that company thinking? Different things matter to different people, and for technical staff employed to manage Linux systems, it’s unlikely they’d choose a Windows desktop. If they did, I’d question whether they are the right people for the role. What makes a great working environment for the best Linux staff? We can start by giving them whatever keyboard, monitor and mouse they want. Add in real coffee, soft drinks and snacks for free. Include remote working for at least some of the time. Oh,…

Every version of Windows enables you to right-click the desktop and create a text file, shortcut and so on. But it’s been removed for all versions of Linux – even Mint, which used to be wonderful. I upgraded to the latest version and now I’m looking for the old DVD. What’s better about removing functionality? Just because Ubuntu pioneers it, that doesn’t mean it’s a good idea. John King, Grimsby, England Jonni says: Icons on the desktop have always irked some people and been a way of life for others. I don’t remember seeing them in Windows 3.1 though… Certain desktops, namely Gnome and the now-abandoned Unity, have decided that we can’t be trusted to keep order on our desktops, and so have benevolently removed that option, although extensions can…

One of the most difficult tasks is to create new and difficult-to-guess passwords, repeatedly. If you don’t use a password manager, you must create such passwords on your own and remember all of them. But if you use a password manager such as the ones on our list, the task of remembering all other passwords can be safely relegated to these tools. This will free you up, if you are that paranoid about security breaches, to choose a password of 50 characters or even more for each account. After all, you don’t have to remember it! The password generator on bitwardencan be accessed from the Tools tab. You can define the number of characters, whether or not you want symbols and special characters, as well as upper/lowercase letters. You can…

1 PSU This is a good a place to start, although smaller cases may require the motherboard (and CPU) be installed first. Some cases allow PSUs to be mounted “upside down” which might allow for a better degree of airflow. Four chunky screws hold the PSU in place. 2 CPU Read the instructions, lift the lever, drop in the CPU, then close the lever. Now read the heatsink instructions and attach any clamps or mountings. Remove the cover from the thermal pad, or apply thermal paste, and install the heatsink. Connect the fan cables to the header on the mobo. 3 Motherboard Fit the backplate in the case. The case may already have standoffs fitted, or you may have to screw these in. Place the board atop them, they should…

One good reason for using Mint as our OS is that it’s based on Ubuntu 16.04, which is one of three distributions “officially” supported by the proprietary AMDGPU-PRO driver. This isn’t usually something to sing about, and this driver is outperformed by Mesa in most games. But the proprietary stack includes a technically superior OpenCL stack, which, amongst other things, makes for faster GPU mining of cryptocurrencies. Modern AMD cards (the RX400, 500 and Vega series) are in general considered better suited to mining than their Nvidia counterparts (although the 1050Ti deserves an honourable bang-for-buck mention). Even the older ones (the aging 7950, and those based on 2013’s Sea Islands and later) can produce impressive hashrates, though they’re not the most efficient beasts. The proprietary bits (500MB of them) work…

While Calamares modules come in all shapes and sizes, Teo believes that perhaps the most technically challenging is the partitioning module. The modules he’s most proud of are those that were contributed by the wider Calamares community: “Some of these modules are just a few lines of Python to handle a distribution-specific quirk, but we couldn’t have made it without them.” Continuing on the same lines, Adriaan points to the downstream modules, that is “stuff that isn’t in Calamares proper, but that distros have developed for their own use.” The one module that, in our experience, hasn’t been widely adopted by the distros is the encryption module. “Assuming disk encryption isn’t used much, I’m going to suppose that either the UI doesn’t match expectations, or the module doesn’t provide the…

By day I’m an A-level student, but by night I organise the Norwich Raspberry Jam. I’m a Norwich Hackspace member, and head electron-wrangler at the Wonky Resistor Co. When I first saw the Pi on the news, I knew it was for me. I got my hands on one, and everything escalated from there! I’ve made quite a few projects over the years: from gesture-controlled mood lighting to game controller kits. This year I hosted two Raspberry Jams in Norwich and co-founded the Young Makers’ Tech Club, a friendly club for kids interested in tech. I also run workshops for beginners and educators, to get them started on their Pi journey. I’ve been fortunate to work with the Forum Trust, which owns and manages a huge building in the centre…

We’ve long been a fan of easygui (http://pythonhosted.org/easygui/index.html).As its name suggests, this is an easy-to-use graphical user interface (GUI) creator for Python, and has many uses. Don’t get us wrong - creating a GUI with Python is relatively trivial thanks to GUI Zero (https://lawsie.github.io/guizero), but easygui gives you a series of predefined functions that will automatically generate the desired dialogs. To test all the dialogs, in the Python shell type the following. As you ll see, easygui has plenty of scope for use in projects that need a quick and simple user interface. These range from file open/save dialogs, button boxes to trigger functions at the push of a button, code boxes that can be used to show the output of an error message intended for standard output and password…

Like any good music player, Volumio supports playlists, but unfortunately it’s not the most intuitive of tools. Switch to the Browse tab and then browse your music library by either artist or album. You’ll see the – – – ’hamburger’ button next to artists, albums and individual tracks – click this and you’ll see an option to add the selected item to a playlist. Either type the name of a new playlist and hit New, or click an existing playlist to add the items to it. You can access your playlists from the Browse tab. From here you can open the playlist to remove individual items via the – – – button, but one crucial missing feature is the fact that you’re unable to rearrange the running order. No problem:…

MPlayercan be a ‘bathtub of code’ sometimes, but it has some brilliantly quirky abilities. On the more conservative side, its -zoom and -loop options make MPlayerideal for advertising displays and art installations (perhaps particularly effective when coupled with a Raspberry Pi?). Here is a video being upscaled and left on a permanent loop: $ mplayer test.avi -zoom -xy 1600 -loop 0 For something quirky, it’s a cliché now, but you can output your videos into ASCII. It’s cheating a bit, but if you want things to look like The Matrix, you can change the video output to ‘matrixview’ with the -vo switch, like so: $ mplayer -vo matrixview test.avi However that’s not really ASCII, it’s a video filter! For true ASCII video (handy if you’re running without X), try the…

This tutorial covers creating a query using LibreOffice’s in-built GUI tools; however, these queries can only display and filter information you’ve requested. They don’t permit you to edit or remove the returned records or add new ones. This is because what you’ve created is called a Select query. In order to add new records you need an Insert query, an Update one to edit existing records or a Delete query to remove them. Microsoft Access converts will be disappointed to learn that there’s no similar method for generating any of those from the Queries menu. For those occasions when you need make a bulk change to your database and only those kinds of query will do, head to Tools>SQL..., write what you want to do as a statement and then…

One of the most useful Gnome Shell extensions for your desktop is Géza Búza’s System Monitor. Once installed on your machine, it displays a compact list of icons in your top bar, representing various system resources such as network usage, storage capacity and swap space. You can click these to view more detailed information about your system. To get started, first click Activites at the top left of the screen and enter Terminal in your search bar. Double-click the Terminal icon to launch it. Enter the commands sudo apt-get update , then sudo apt-get upgrade to bring Ubuntu fully up to date. Next enter sudo apt-get install gir1.2-clutter-1.0 . Choose Y to confirm that you wish to install. Once this is done, open your web browser and navigate over to…

Our expert Mark Chisholm is wondering if he will experience something like the Tetris effect after having written the word ‘desktop’ so often in this article. Only time will tell… Were you to ask people what their favourite part about Linux is, they would probably say that they enjoy its stability and performance. They might also say that they like its security. It excels in all three areas due to the heavy influence of the UNIX operating system. Its modular nature means that even if one part of the Linux system fails, all the other packages and services running on the system will keep going. The thing we enjoy most about its modular nature is that it can be pulled apart and put back together. While there are Linux distributions…

Our expert Dr Sinitsyn is a lapsed KDE committer with 0.16 GSoC pupils per year, so he has plenty of time to build Linux clouds and write words. The best language ever? Which scripting language is the best? Obviously, it depends on whom you address. For a veteran systems administrator, shis a way to go. Should you ever need more, awk and sed are always here to help. Oh, and there’s also Perl, in case you have forgotten. “No-no-no”, his younger colleague says. Nobody wants to code in a language which doesn’t even know the difference between [ and [[. Even with newer implementations such as Bash, shell scripts are clumsy, unreadable and full of black magic. The same stands for Perl, and you never hire a guy who knows…

“The new Firefox is blazingly fast: twice as fast as Firefox 56” Web browser Firefox Version: 57 Web: www.mozilla.org Mozilla’s flagship product has been hitting the news headlines recently thanks to this new release, which we really couldn’t miss. Even though HotPicks deliberately avoids reviewing such open source celebrities as Firefox or LibreOffice in order to shed light on less well-known applications, this time it is a different game. In recent years Mozilla introduced a well-thought-out approach to its release policy: everyone who needed a stable, modern, yet not-so-rapidly-changing browser was advised to use the Firefox ESR edition, while the rest could enjoy the regular Firefox version, which gradually evolved from one release to another. This time Firefoxsays goodbye to rounded Australis-styled tabs (introduced in late 2013) and rolls out…

Our expert Mats Tage Axelsson has been making Linux machines work since version 0.99, and is a regular and reliable contributor to Linux Format. We like you, Mats! Android Studio gives you plenty of options, but to choose the correct platform you may need to tweak your environment. The default setting is API 21 that corresponds to Android 5.0 (Lollipop), which means most devices are compatible. If you want more features, step up to a newer system, but be prepared to lose users on older devices. Developers want to create an application for the masses, collect the winnings and then retire to a tropical beach sipping a mai tai. But in the real world, we have projects that need to be designed for a range of older devices. In fact,…

Our expert Mihalis Tsoukalos is multitalented: he’s a UNIX administrator, a programmer, a DBA, an expert mathematician and the author of Go Systems Programming. You can reach him at www.mtsoukalos.eu and on Twitter at @mactsouk. This month’s tutorial will cover functional programming, which means working with functions and using functions like variables. We’ll look at higher-order functions, closures, inline functions, anonymous functions and will describe a function that returns another function. If this is the first time you’ve tried this programming paradigm then you might find functional programming difficult, but you certainly won’t regret learning more about this new way of thinking about programming. So let’s get started exploring the functional capabilities of Kotlin. Functional what? Functional programming is a programming paradigm, where functions are first-class citizens such as variables…

RTFM was the battle cry of old, particularly in the days of Unix but carrying over into Linux. Standing for Read The Fine Manual (or something like that), it was a stock response from those who thought they knew it all to anyone who asked a simple question without checking the documentation. Fortunately, the Linux community is a lot more civilised these days. Additionally, the distros have come on leaps and bounds in all areas of the user interface, so there’s no longer the need for many of the basic “How do I…” questions. Is TFM heading for extinction? Absolutely not. While software becomes more accessible, they’ve also gained more features. So you can use most programs without reading the documentation, but using them effectively is another matter. Open source…