Indholdsfortegnelse for September 2017 i Linux Format

Alex Cox Forget RTFM: dive in head first. Drown slightly. Find some poor sap who also has lungs full of water, and determine how they coughed it up. Dive in again, and repeat the process until one has transcended the water metaphor completely. Nate Drake I’ve become a great fan of the method of Loci ,whereby you visualise objects placed in locations around somewhere familiar to you. This is a particularly good way to learn long lists of information. You can combine this with a peg system, whereby some objects represent numbers if necessary. Nick Peers Unfortunately, I have to admit my favourite tool for learning is DuckDuckGo. Fifteen years of answering reader questions has taught me that it’s not what you know, it’s how to search for the right…

“In July 2017, new and old members of the GNOME community met in Manchester to discuss the future of the Linux desktop at the latest edition of GUADEC, the annual GNOME Conference. While the schedule was packed with great talks, the highlight of the week was undoubtedly the main event celebrating the 20th anniversary of the GNOME Project, enhanced by the presence of one its co-founders, Federico Mena Quintero. With Ubuntu having recently decided to move to the GNOME 3 desktop, and Endless re-basing their desktop to a more recent version, 2017 is turning out to be a year of reunification for the project, bringing new energy and excitement that could be felt throughout the conference and a united GNOME platform for developers to build on. A number of improvements…

Penwortham Makersphere Pupils, projects and primary school learning. When thinking of technology, St Mary Magdalen’s Catholic Primary School, Penwortham near Preston, may not be the first place that you think of. But on July 15th the school was full of tech! Makersphere was created in 2016 by Lara Lowe, a Raspberry Pi Certified Educator who wanted to create an event where parents and children can learn how to use the many different technologies on offer. Over the course of the day there were sessions using the Raspberry Pi, Codebug, micro:bit to create many different projects. Classrooms became hubs full of eager families, children showing parents how they can hack their ideas to life. One of the best sessions was Codebug, where children built circuits using crocodile clips and LEDs. This…

Just when did ‘command line’ stop meaning runlevel 3 and start meaning: boot the kernel, login, startx, set up the desktop and then open a terminal window? The analogy that springs to mind is extolling the joys of cycling by proposing to mount a bicycle inside a van in order to take it on the road. <end_rant> Apart from that you’ve got a great magazine. TE Groves, via email Neil says: What springs to mind is that at home we call watching the tablet, watching TV to the children. It’s just a handy shorthand, but you’re right of sorts. I think that we tried to explain this at the start of the article, but attempting to explain runlevels to beginners can become something of a long aside that doesn’t help…

Fedora 26 also includes the new DNF (Dandified yum) 2.0 package manager, which still respects yum’s syntax. The yum command is actually symlinked to DNF, but it works exactly as it used to, so if you don’t want to learn new syntax then you don’t have to. DNF is smarter and faster than its predecessor. It supports delta packages (DRPMS) so that only those parts of the packages that have changed need to be downloaded. Obviously, this works better with some packages than others, but the handful of updates we performed saw bandwidth savings of between 10 and 40 per cent. Users of Debian-based distros will be shocked to hear that there’s only one command – dnf upgrade –for upgrading the system, rather than the familiar apt-get update && apt-get…

A clear advantage of using a dedicated file store is its ability to keep previous versions of a modified or deleted files. SparkleShare is based on the Git version control system. Its system tray icon keeps track of changes to the files and can be used to restore an older version as well. On the downside though, it doesn’t enable you to tweak this behaviour. Seafile, too, takes periodic snapshots of files, folders and entire libraries that can be easily restored with a single click. Although it keeps a full history by default, you can specify for each library a period of time for which you want to keep old files. You can browse the history of a file and restore the file contents to a previous version. As per…

Step Part of the KDE Edu bundle, Step is a physics simulator. You can place particles, springs, motors, all kinds of things, then hit Go and the situation evolves according to the laws of physics. This teaches you all about Newtonian mechanics and soft bodies in a manner much more mesmerising than lists of formulae. Gcompris An educational suite, Gcompris was originally for Gnome, but is now rewritten in Qt. There are over 130 ‘activities’ (games) aimed at 2–10-year-olds, but some of them are fun for grown-ups, too. It teaches all manner of things, from basic computer proficiency to jigsaw-style puzzles involving Van Gogh paintings. Scratch Developed at MIT, Scratch teaches programming visually by connecting blocks together. This is a lot more friendly than having to manually write code (and…

Arduino boards have proved very popular in the maker community, thanks to their affordability, low power consumption and open source nature. However, a schism and trademark battle has dogged and fragmented the community. Until recently, there were two companies: Arduino LLC (http://arduino.cc, created by the five co-founders of the Arduino project) and Arduino SRL (http://arduino.org, formerly Smart Projects, set up by Arduino co-founder Gianluco Martino, and most recently headed by Federico Musto). At one stage, the LLC entity was forced to introduce a new (European) trademark, Genuino, to protect distributors from litigation. The two firms officially buried the hatchet last year, with all trademarks transferred to a new holding corporation, Arduino AG. Those trademarks have now been acquired by BCMI, a group set up by the four co- founders, excluding…

Once enabled, Ufw will launch on startup, blocking all incoming connections and permitting all outgoing ones. This might not be ideal if you like to connect to your Pi via SSH or VNC. To configure Ufw, use Terminal on your Pi. Ufw recognises most services like SSH, so in most cases you can enable access using ufw allow – for instance: sudo ufw allow ssh To see a full list of services you can enable in this way, simply run the following command: nano /etc/services If your service isn’t listed, open the port it uses. For instance RealVNC, which can be used to connect remotely to the Pi’s desktop, runs on Port 5800. To have Ufw open it, run: sudo ufw allow 5800 To enable connections only from a specific…

Pipes are special operators that are designed to redirect the output of one program into another command for further processing – typically to produce a different form of output. Pipes are formed using the | character, which is found by holding Shift as you press the backslash (\) key on most keyboards. The following example pipes the result of the ls directory listing command to the less command to produce a more screen-friendly format: Here’s a clever use of the wc (word count) command and -l flag (list the number of lines) to list the number of objects in the listed directory: Pipes aren’t simply used to display the output from one program in another. The following example enables you to download a video from YouTube and then run it…

The Linux ecosystem boasts of several distros dedicated to hobbyists. Whether you’re into gaming or graphical design, there’s a Linux distro tailored for that specific use case, with a host of apps and tools designed to aid you in your adventures. Budding musicians and hobbyists will appreciate the richness of tools, utilities and apps available for Linux. Like LMMS, Ardouris popular Digital Audio Workstation, but it isn’t as beginner friendly. Once you’ve mastered LMMS, and have a fair understanding of the music making process, you can venture into Ardour. If you’re interested in learning music theory in order to better understand what constitutes a melody, Phonascusis the tool for you. This program boasts several lessons and exercises to help you identify notes, scales, intervals, chords and much more. If you’ve…

1 Configure scalpel Open Terminal and run sudo apt-get install scalpel to install scalpel. Next run sudo nano /etc/scalpel/scalpel.conf . Scroll down to the file type that you need to find and uncomment the line by removing the # at the start of it. Repeat this for as many file types as you want to recover, then press Ctrl+X, Y, and then return to save and exit. Scalpel should now be ready to use. 2 Begin file recovery  syntax scalpel scalpel <drive> -o <output-dir> , for example sudo scalpel /dev/sdb1 o /home/nate/scalpel-files . You’ll need to use sudo to scan a drive, but you can analyse disk images with a standard user account. This takes some time depending on the size of the volume and number of files. Once it…

Unfortunately, if you’re using Fedora 23 or later as a guest OS Ansible support is slightly broken. This is because the distro no longer ships with Python 2 and Ansible needs this for the RPM install module to work. As a consequence, if you try to run Ansible you will simply get error messages about missing Python modules. Until Ansible migrates to Python 3 (a release supporting it was under active development at the time of writing) you can work around this problem by sending raw commands to the package manager instead: The downside to this approach is Ansible has no awareness of whether your applications have been installed successfully or not, and it also has no idea whether your system is running the latest versions. As a result it…

Android Debug Bridge, or ADB, is essential for deep-level communication with your phone’s operating system, and fastbootdeals with communicating with your phone’s bootloader. Head to a terminal window on a machine running a 64-bit OS (there’s no longer 32-bit support) and download the tool package containing both with wget https://dl.google.com/android/repository/platform-tools-latest-linux.zip, then unzip it with unzip platform-tools-latestlinux.zip. Now edit your bash user profile file by running sudo nano ~/.profile and add the following to it to ensure the adband fastboot commands are available from everywhere: if [ -d “$HOME/platform-tools” ] ; then export PATH="$HOME/platform-tools:$PATH” fi Reboot your machine, and the Linux side of things should be done – now it’s time for you to set your smartphone or tablet up. On your device, open Settings > About and then dig down…

Our expert Adam Oxford  a based in South Africa. As well as producing media using open source tools, he trains journalists in online security and data-driven storytelling. Serial, Freakonomics Radio, TWiT, My Dad Wrote A Porno: the humble podcast is entering something of a golden era, with both the variety and quality of audio productions at an all-time high. Yet despite being one of the internet’s oldest and most enduring formats, the longevity of the podcast in the era of Facebook, YouTube and Twitter was at one time in question. Surely modern audiences didn’t have the patience for challenging audio documentaries? Could radio-type humour survive the onslaught of funny cat vids? Fans should worry no more. Last year the number of podcast listeners increased by 23% in the US alone.…

As you saw from the implementation of sortArrays.py, having more constraints or knowing more information about the data is usually a good thing that can help and simplify your implementation. Additionally, the code of sortArrays.go is much faster and straightforward than the code of multipleScans.go because you know that your numeric data lies within a given range, there are no duplicates and you have more memory space than in multipleScans.go. The general advice here is that you should always try to learn more about your data and use that information to your advantage because having a simpler design in your software is always a good thing! Spending too much time trying to find patterns and limitations in your data and trying to understand your data is not always a good…

You’ll be able to get going on Lambda and spend just a few dollars at most, all of which would be on bandwidth and storage. Lambda’s free tier includes 1M of free executions and 400,000 GB-seconds of compute time per month. Computing is charged in GB-seconds, which means the more memory your process uses, the more expensive it is, but I wouldn’t optimise too early since 1536M costs a mere $0.000002501 per 100ms of execution and you get 266,667 executions for free. The other costs you’ll incur are bandwidth (to the API endpoints and S3), storage on S3 (which may be large if you’re storing huge amounts of data) and other compute or data services such as RDS. It’s likely that more consistent demand applications like blogs and e-commerce sites…

Encryption tools Transform your most precious files into seemingly innocent background noise with open source software. Snap attack! What’s all this fuss about Snaps? It’s time to find out, as well as look at the new way to package programs. Swap is dead, long live swap As Ubuntu declares the swap partition is long gone, we try out the new (but old) file-based system. OggCamp, baby! We (well, Les Pounder) reports live from the boisterous unconference that returns under new management! Contents of future issues subject to change – we might be too paranoid to come out of the shadows.…

To quote Natalie Portman, “Learning is beautiful.” Isn’t that the truth? If you’re reading Linux Format, you undoubtedly have the same sentiment; that’s the beautiful thing about using Linux and open source – the continuous learning curve. Just as you think you’ve mastered one area, a whole new technology appears for you to tackle. With the Raspberry Pi Foundation’s mission to push coding into the curriculum, Linux powering more areas within schools, and open source becoming an increasingly important area, we’re dedicating our back-to-school issue to explaining how you can use Linux, open source and low-cost single-board PCs to power your own and children’s education at school. We’ll look at how you can outfit a laptop with the ideal selection of educational FOSS tools that’ll stay with you for life,…

GNU Privacy Guard (https://gnupg.org), also known as GnuPG, is a vitally important encryption software program that many people around the world rely on to protect their emails and other digital communications. It’s especially important for activists, journalists and lawyers in countries ruled by oppressive regimes, but unfortunately since 2012 it has encountered a number of funding crises that have impacted the project and the number of people who can work on and continue to develop it. Previous rounds of fund raising has allowed the project to take on five additional developers, while adding new features such as Python bindings and improvements to Enigmail (www.enigmail.net). However, to carry on this vital work, GnuPGis asking for more donations, with a primary goal of raising €15,000 a month – with a stretch goal…

RED HAT ENTERPRISE LINUX 7.4 The latest version of the enterprise-class distro also commonly known as RHEL has been released, and this new update brings a number of tools to help combat modern IT infrastructure threats. According to the press release (www.redhat.com/en/about/press-releases/ www.redhat.com/en/about/press-releases/red-hat-bridges-hybrid-multi-cloud-deployments-latest-version-red-hat-enterprise-linux-7 www.redhat.com/en/about/press-releases/red-hat-bridges-hybrid-multi-cloud-deployments-latest-version-red-hat-enterprise-linux-7 www.redhat.com/en/about/press-releases/red-hat-bridges-hybrid-multi-cloud-deployments-latest-version-red-hat-enterprise-linux-7 red-hat-bridges-hybrid-multicloud-deployments-latest-versionred-hat-enterprise-linux-7), “Red Hat Enterprise Linux 7.4 offers new automation capabilities designed to limit IT complexity while enhancing workload security and performance. This provides a powerful, flexible operating system backbone to address enterprise IT needs across physical servers, virtual machines and hybrid, public and multi-cloud footprints.” For a full list of new features check out https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/7.4_Release_Notes/index.html. BACKBOX LINUX 5 BackBox Linux 5, the new version of the Ubuntu-based distro, has been released. BackBox Linux is a distro designed for penetration testing and other advanced security tests, with…

Crafts Council Each year at the end of October the Crafts Council runs a weekend-long event across the UK. Make:Shift:Do is a celebration where makers throw open their doors and invite the public to see what they make. This event is open to all maker/ hack spaces, nationwide. You are encouraged to offer a project for the weekend, which will engage the public and show how the act of making can be used to encourage better health. Take part and to learn more: http://www.craftscouncil.org.uk/what-we-do/makeshiftdo/ Pi Birthday 2018 The Raspberry Pi Birthday event takes place in early March each year. But for 2018 there will be a change of format. Rather than a large central party, Raspberry Jams around the world are encouraged to host their own parties and link up…

Uploading your data to a server is only part of the story. You also need a choice of cross-platform clients to interact with the server, ideally in a seamless fashion. SparkleShare is limited in this department because while it has desktop clients for Linux, Windows and Mac OS X, there’s no mobile client functionality. It sits in the system tray and displays notifications about the synchronisation operations as well as a list of any changes that occur across all shared directories. Syncthingis essentially a CLI utility wrapped around a browser-based interface. But the project also hosts a Python-based cross-platform graphical interface and a notification area icon that exposes all of Syncthing’s features accessible via the browser. In addition, there’s a functional mobile app for Android. Similarly, along with Debs and…

Besides the storage servers we’ve tested in this Roundup, there are lots of options that you can use to share data between multiple computers and devices. For starters there’s ownCloud, which is the progenitor of NextCloud. It’s still going strong despite the departure of its core developers, but the speculation about its uncertain future hasn’t completely died down. Then there’s Git-annex, which syncs files using Git. Another interesting option is StackSync, which stores the actual encrypted data on a public cloud like OpenStack Swift or Amazon S3, but keeps the associated metadata inside your network. Alternatively, if you aren’t averse to proprietary software, there’s Resilio Sync that relies on a modified version of the BitTorrent protocol. You can, of course, also use a NAS solution that performs pretty much the…

Part of the reason for Chromebooks’ popularity is that they have seen extensive adoption in the classroom. They have a low price tag (except the fancy ones), an impressive battery life, yet enough power to deal with word processing, web browsing and whatever else it is kids do. Students have not been dissuaded by their lack of storage, since once you get into the mindset of saving everything to the cloud, it becomes second nature, and obviates the old problems of keeping track of multiple versions of a document, or saving it to a dodgy USB and losing it for ever. Nor are they concerned about their devices being stultified where internet access is not available, presumably because they don’t go to such places often. There are benefits of having…

They say the best way to learn is to do – and what could be more fun than tackling a few projects? We’ve chosen three that will not only help you learn coding and enhance your knowledge of electronics, but also introduce you to the most exciting and popular devices used in schools, as well as in the real industrial world. This isn’t just about dull education: these are real-life tools that are changing the planet. The world of single-board computers and microcontrollers is awash with designs, all promising to be the next step in the evolution of Making and learning. But if you are new to this area, you really just want to stick with the big three: the Arduino, micro:bit and the Raspberry Pi. Support (and openness) is…

Using the Raspberry Pi GPIO (General Purpose Input Output) can seem scary at first. But fear not: using just 19 lines of Python code, you can create a graphical user interface (GUI) to control a real-world LED and buzzer. Building the circuit for this project is relatively straightforward: just follow our diagram and check each connection as you go. When all of the connections are made, connect your accessories and boot your Raspberry Pi to the desktop. We will need to install one piece of software before we start coding. Open a terminal (the icon is in the top-left of the desktop) and type: Close the terminal when installation is complete. We are using the latest Raspbian image, which comes with Thonny, an easy-to-use Python editor. You can find this…

“The UBports community aims to breathe life back into Ubuntu Touch” There are some two billion phones out there running Linux right now in the form of Google’s Android. But an aging Linux kernel buried beneath several layers of Java and a proprietary app store does not a free mobile utopia make. The demise of Ubuntu Phone, not to mention other mobile efforts falling by the wayside, was a blow for hopes of a more open mobile platform – but hope is not lost. The UBports community aims to breathe life back into Ubuntu Touch, and has already shipped its first update. Many other projects are alive and well at the hardware level, and at various levels in the software stack. Android has been around for long enough that people…

Our expert Nate Drake Nate used to top up his meagre income by offering a document recovery service using scalpel. His first customer was a burlesque dancer. It pretty much went downhill from there.… You probably remember the news. In December 2016, the BBC reported that the infamous Mirai worm had infected a substantial number of routers used by customers of UK ISP TalkTalk, stealing their Wi-fi passwords. The worm exploited the default admin passwords that are hardwired into a number of machines, and although the focus was on enslaving devices to take part in DOS (denial of service) attacks, the implications are staggering. Even those handful of users who take the trouble to change their router’s default passwords seldom bother to use firewalls. In plain English, this means your…

Our expert Shashank Sharma Shashank Sharma is a trial lawyer in Delhi and avid Arch Linux user. He’s always on the hunt for geeky memorabilia. At the expense of being confused by yet another binary joke, and without dwelling in musical theory, let’s all agree that there are two types of music:. All your favourite musicians, be it Led Zepplin, Madonna, the Beatles, Steps, and the rest are one type – vocal. The other type, comprising solely of instruments, is more commonly used for films and television. Productions such as The Terminator, Star Trek, Game Of Thrones and Sharknado use the latter to create a signature tune, often played during the opening or end credits. With LMMS, which features a song editor, beat editor, piano input, support for MIDI keyboards,…

Our expert Nate Drake Nate used to top up his meagre income by offering a document recovery service using scalpel. His first customer was a burlesque dancer. It didn’t end well… Those readers lucky enough to have been designated their Family’s Tech Support Liaison may be aware of their loved ones tendency to store what we euphemistically call Schrödinger’s Data. This term is used to describe personal files such as photographs, calendars and documents that are apparently absolutely essential to their wellbeing, but paradoxically aren’t important enough to back up. The end result is that if an essential file is deleted by accident, there doesn’t seem to be any easy way to recover it. In reality, most reasonably IT literate people know that many computers don’t erase files fully and…

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. When you hear the name ‘Vagrant’, you might be wondering what rough sleepers have to do with managing virtual machines (or VMs, as they’re known). You would be in good company, because as far as strange project names go, this has to rank favourably with competition like ‘Kafka’, ‘Avogato’ and ‘Mustache’. To clarify, Vagrant is a common scripting language for managing and provisioning virtual machines across different virtualisation tools like Virtualbox and VMware Workstation. It relies on drivers to translate the instructions you provide in the configuration (such as your choice of operating system, number of processor cores, amount of…

For those who are unfamiliar, Wine is an emulation layer that sits between a Windows program and Linux, and attempts to translate the instructions between them in real time. You can install supporting libraries and customise compatibility settings on an application by application basis using separate wine “prefixes” that behave like their own install directories. Unfortunately, because the community doesn’t have access to the source code for Windows, this is far from a perfect system. While there has been progress made on compatibility for common applications such as Microsoft Office, Internet Explorer and Adobe Creative Suite, your mileage will vary. You can find out how well an application is likely to run from https://appdb.winehq.org. Another downside is it’s not isolated from the host system, so you could find your home…

What we’re doing here is absolutely destructive. Flashing new firmware onto your phone means your old firmware, the stock OS that came with your device and everything you’ve added to it since, will be erased, and while we’ll take backups along the way there’s no guarantee of them catching everything. If you’re flashing your main phone, that means that your phone book will be gone, your photos; everything. And should something go wrong during the process, there’s even a possibility you’ll brick your device; that is, the process could make it as useful as a brick. We’re absolutely not trying to scare you away, but it’s sensible to be aware of the realities, and sensible to take the right precautions. Make sure, to begin with, that you’ve fully backed up…

We’ve shown that it’s possible to record multiple microphones directly into Audacity, but there’s no getting around the fact that a mixing desk isn’t just easier to set up, it’ll give you more control over recording levels and the end result will be more professional. The good news is that while studio equipment is expensive, you can pic up a four track mixer from Gear4 for as little as £40. Cheaper mixers may not have as many XLR inputs for microphones, but judicious use of XLR-1/4” jack adaptors can get round this. The more you can spend on microphones, the better, but don’t feel you have to spend hundreds on a professional dynamic mic if you’re starting out. A condenser mic is cheaper and, because it’s less sensitive, won’t pick…

Our expert Mihalis Tsoukalos Mihalis Tsoukalos is a DBA, a UNIX Administrator, a Programmer and a Mathematician. You can reach him at www.mtsoukalos.eu and @mactsouk. The main subject of this tutorial is finding out ways to sort data using a limited amount of RAM. However, you are also going to learn how to read text files line by line in C, Go and Python 3 as well as how to sort numbers and strings, which is not a small amount of knowledge for such a small tutorial! Once again, if you want to get the most from this or the previous tutorials of Linux Format, you should first try to think about the problem on your own and come up with some possible solutions that you should try to implement;…

Our expert Dan Frost Tech Director at 3ev.com, writer and explorer of ideas and tech, Dan is often found on twitter @danfrost dismissing (then championing) new computer fads. Serverless computing offers the ability to build scalable, production-ready code without the need to deploy or manage servers at all. For many of us, this is what cloud computing was always meant to be: no longer thinking about servers, paying infrastructure and managing complex scaling rules. You can use Serverless programming to build backends for apps, websites, virtual reality, data pipelines and more. In fact, pretty much anything you can build on a server you can also build Serverless. In this tutorial, we’ll see how to use Serverless programming to build a basic data pipeline that checks for interesting or suspicious lines…

The popular RPCS3 PlayStation 3 emulator has now come to Linux, and after a difficult development period (the creators admit that earlier this year “quite literally nothing was working”), it has now reached compatibility and stability parity with Windows. On the project’s website (https://rpcs3.net), it shows a number of PS3 games running on various Linux machines. If you’d like to find out more about playing your old PS3 games on Linux, check out the quickstart guide at https://rpcs3.net/quickstart. We won’t go into the morality of emulating games you don’t own here – we’ll just leave that up to your conscience. Mozilla has got good news for people who hoard tabs while browsing the internet, with the upcoming Firefox 55 (which is in beta) able to handle a huge amount of…

“LinuxCon, ContainerCon and CloudOpen have brought thousands of open source professionals together in Europe for years. In 2017, these events have combined with the new Open Community Conference and Diversity Empowerment Summit under one umbrella name: the Open Source Summit. The event will take place on 23-26 October in Prague. Open source has expanded to become the default method of software development in just about every area of technology, so we felt it was time for a new event that retains the great technical and business content we have offered for years but in a way that is inclusive of all types of projects, technologies and community members. At Open Source Summit Europe, attendees will collaborate, share information and learn across a wide variety of topics, with 2,000 technologists and…

Famous! The crossword puzzle in The Spectator (18 February) contained the clue, “Wife after course wanting electronic operating system (5)”. It looks as if Linux has made it into the public consciousness at last. Keep up the good work. Chris Watts, via email Neil says: What a spot! I think I remember spotting that Emacs had made it into the New York Time crossword. I believe the clue was “Partner of vim.” MOAH 3D! Imagine taking a 3D project across the different software programs. For modelling you could use Blender, 3ds Max, Rhino, SolidWorks, FreeCAD. Fixers: Blender, MeshLab and Netfabb (Basic). Across the varying print processes and printers (from low end to expensive) there’s Shapeways, Sculpteo, 3D Hubs and home printing. For materials you could use plastic, PLA, metal, acrylic…

Like with all server software, a healthy support infrastructure plays a key role in its adoption. SparkleShare is the lone exception here in that its documentation and support pales in front of its competition. While it’s the only option that features installation instructions on its main page, there’s very little information elsewhere that’ll help guide a first-time user. The project’s website features a wiki with just about enough information that’d make more sense to a Git user. On the other hand, the intuitive Seafilehas detailed documentation on its website to take you through all its features and tasks. Similarly, Syncthing has documentation that covers everything from basic usage to advanced configuration. There’s also information about the CLI utilities and a detailed FAQ. If the documentation doesn’t resolve your query you…

“Parents may find questions about Python more terrifying than those about Pythagoras” The sun is setting earlier and parents can almost taste the 6.5 hours of freedom that go with their progeny returning to school. Those with offspring heading to university have even more free time to look forward to. But spare a thought for those students who face social pressures, a gruelling curriculum and an environment that can unnecessarily coerce them into proprietary ecosystems. The UK curriculum revamp in 2014 replaced the mickey mouse, Microsoft Office-centric Information and Communications Technology (ICT) syllabus with a more solid Computing one. In some schools, pupils as young as five are learning the beginnings of coding. This presents challenges not just for students, but for parents, too, who may find questions about Python…

“There are two education-specific distros: Edubuntu and Uberstudent” Whatever subjects you or your spawn are studying, you’re going to need to edit some documents, maybe mess with some spreadsheets, and perhaps make presentations, too. To that end, LibreOffice is very much your friend. There’s a fair amount of slanderous cant uttered about this awesome software, and we’d really like to set the record straight. Firstly, MS Office and LibreOffice are format compatible. Word files will open in LibreOffice Writer, and vice versa. Anyone who tells you otherwise is lying; MS Office has supported OpenDocument file types since 2007. Even the UK government has endorsed OpenDocument as the standard file format for use across government operations. That said, LibreOffice is not Microsoft Office, and occasionally you’ll find a document that doesn’t…

1 Arduino This open-source project, started at Interaction Design Institute Ivrea, in Italy. Created to help students add interactive features to their work, the Arduino was priced “as much as a good meal and a glass of wine” (not in Bath–Ed) to make it affordable. Using an ATMEL microcontroller, the Arduino powers thousands of projects. 2 Raspberry Pi With over 14 million units sold since 2012, the Raspberry Pi has disrupted the world of single-board computers. This $35 computer has gone from a mere curiosity to a global phenomenon that has kickstarted a desire to learn and create with children and adults. At its heart is a low-power ARM CPU, and a lightweight Linux-based operating system. 3 micro:bit The micro:bit project arrived in late 2015, and is a ARM-based microcontroller…

First, build the circuit as per the diagram, then plug your Arduino into a spare USB port. Install the Arduino editor on Linux, using the excellent guide at www.arduino.cc/en/Guide/Linux. Open the Arduino application. The Arduino has code that runs once, typically in ‘setup’, and code that runs continuously in ‘loop’. Just before our setup we will add three lines. The first creates a variable, the pin number used to connect our ultrasonic sensor; the second line imports the LCD library; and the third tells the Arduino which pins connect the LCD. Inside the setup section we create a serial connection, to debug any errors. We instruct the Arduino that we are using a 16-character-wide and 2-line LCD screen. On the screen we will print a “boot” message, then pause: Inside…

“GPU acceleration works very nicely on many modern video chips” Video editor Shotcut Version: 17.06 Web: https://shotcut.org Exploring the world of open source creative software quickly reveals that there’s a visible demand for non-linear video editing. Regardless of the way people use such software, the number of available titles keeps growing, and already includes such respected names as Kdenlive, OpenShotand Flowblade. But there’s another application that we undeservedly missed: Shotcut. In the endless line of ‘shots’ and ‘cuts’ software, this new editor combines simplicity with a decent set of features, and we’re sure it will attract devoted users that find other editors too complicated or basic. Shotcutoffers a neat and compact Qt5-based interface, and makes use of such technologies as FFMpeg, MLT, x264 and LADSPA, as well as various encoders.…

Hi, I’m Andy, and I live in Amsterdam with my wife and kids. I’m a web designer but I love to tinker with the Raspberry Pi! I’ve been working with Linux for close to 20 years, firstly as a web designer and developer, working with the traditional LAMP stack, and more recently I’ve dug into physical projects with the Pi. A year ago, I picked up a Pi 3 for a retro arcade build I was working on with my son, then I found myself looking for more opportunities to mess around with hardware. Since then, I’ve completed a bunch of increasingly more challenging projects, including squeezing a Pi Zero W into a SNES controller and building a custom network speaker for our living room. I’m now working on a…

Our expert Nick Peers has been playing around with computers for over 30 years, and has been dabbling with Linux for the best part of a decade. The art of command chaining is simple: multiple Linux commands are combined into a single line. The obvious use for a chain is to run multiple commands one after the other, enabling you to leave a lengthy process to its own devices without having to intervene. For example, quickly check for updates and install them using the following chained command: $ sudo apt-get update && sudo apt-get upgrade The && that separates the two commands is known as an operator, and Linux provides you with a choice of different operators, enabling you to control how each command in the chain behaves based on…

Its graphical nature and the ample presets and samples may give the impression that it’s easy to create tunes with LMMS, and it is. Unfortunately, it’s not so easy to create good, melodious, memorable tunes. If you have a good ear, you can go far with LMMS without ever taking a deep dive into musical theory. But you’ll still need plenty of help along the way. The FAQ hosted on the website is a good starting point. It’ll help you understand how you incorporate the presets into your first project. Although now thoroughly out of date, LMMS: A Complete Guide To Dance Music Production, published in 2012 by PacktPub, can also provide useful assistance, but it’s best to first explore the manual and the Getting Started guide hosted on the…

Docker is a containerisation technology that isolates applications from each other while using the same kernel. The main benefit, if you’re not a developer, is that it can enable you to run an application packaged specifically for Ubuntu on Fedora without compatibility problems. However, it is worth bearing in mind that it can still make changes to the host system from within docker, so you should be mindful about the packages you choose to run this way on your home setup. Much like Vagrant there is such a thing as a “DockerFile” that works in a similar way to a Vagrantfile. You can find out more information about this via http://dockr.ly/1PallBK. Docker is one of the virtualisation technologies that Vagrant supports, but you can also use your Vagrantfile to deploy…

Our expert Alex Cox Part computing writer, part harassed father, part breaker of things, Alex has been hacking his hardware since he first took his ZX Spectrum to bits. Money changes everything. In the case of super-popular Android OS fork Cyanogenmod, money changed its parent company’s philosophy, changed its direction from one of free software development to one of commercial software licensing, changed the company’s CEO and project leader – it’s still not entirely clear if he left or if he was pushed – and an eventual lack of money led to Cyanogen Inc. cutting back drastically on its operations and completely dropping support for Cyanogenmod. It also led to the community, which had been hugely involved in its development, snatching back its baby and rechristening it. Thus we now…

Installing an open-source OS and then immediately installing Google apps could seem counterproductive; the ‘open’ part of OpenGApps refers to the project itself, not the apps, and if you’re in this for freedom rather than a phone refresh then immediately undoing that good work with a package of proprietary software is a mad move. Thankfully there are many who share that philosophy, and a stack of open-source apps available for those who want them as part of the F-Droid project. F-Droid is essentially a repository for open-source software, and you can use it to install a host of non-proprietary apps. You won’t find it on Google Play – there are obvious philosophical differences going on – but anyone can use it, even if you’re using a stock Android phone or…

Mixing two mics together in Pulse requires installing PulseAudio Volume Control (PAVP). You’ll find this in your Software Centre in most ditros, or you can install it from the command line with sudo apt pavucontrol . Open up PAVC, and go to the Input Devices tab. You’ll see a separate volume monitor for each input. Now open a terminal with CTR+ALT+T and type pactl load-module module-null-sink sink_name=mixtrack . You should see an extra line appear in the Input Devices tab, called ‘Monitor of null outputs’. You may need to change the Show menu at the bottom of the screen to ‘All input devices’. Now, we need to feed something into the monitor channel. Go to the ‘Recording’ tab, which should be a blank screen. Then, type pactl load-module module-loopback sink=mixtrack…

The coding challenge in this issue of Linux Formatis about sorting data with a limited amount of memory, which as you can understand is pretty challenging because we are all used to having lots of memory on our machines and not worrying about RAM at all. Apart from the memory constraints of the problem, we will add more constraints to it as an attempt to make the problem more interesting and the code simpler. Don’t forget, however, that simplicity comes at a cost: the price you pay for simplicity is the extra time you spend thinking about the problem and its constraints. Can you think of a better technique to sort data with a limited amount of memory? Let us know and you might find your code published in a…

Our example uses already installed Python libraries (boto3 and logging), but if you’re doing imagine manipulation, machine learning or other tasks that involve additional packages or binaries you’ll have to install them yourself. But how when you don’t have access to the server? You do it by saving the libraries into the root of the project. So, if you want to use numpy, for example, you add it in the main Serverless project folder. I’ve found that symlinking to external libraries is a far cleaner way to manage many dependencies. See more on the ‘package’ option for serverless.yml to make sure your libraries are included. I often use unzip -l . serverless/*.zip to list everything that’s being uploaded just for a sanity check. Binaries are more involved but the principle…

All three distros on this month’s DVD share a common heritage – they can all trace their roots back to Red Hat Linux, though they each present a different user experience. We often hear about projects being forked, sometimes by disgruntled developers who think they know better (and sometimes do – look at what happened when XOrg was forked from XFree86). One of the complaints is that forking causes fragmentation, and this may be true in the short term. But the usual outcome is that either the fork or the original flourishes, usually though better code or support, and the other withers. Forking is really just a form of evolution, the software world’s equivalent of mutation, but projects don’t only fork. Two of the distros on this month’s DVD are…