Linux FormatAugust 2018的目錄

Jonni Bidwell I remember fondly, from my time as an apprentice algebraist, learning LaTeX and no longer having to suffer the indescribable horrors of Microsoft’s Equation Editor. I also recall the subsequent horrors fighting with this typesetting kraken as well as its cursed partner in awkward capitalisation, BibTeX. What were they thinking? Bobby Moss Mastodon helped me escape the swirling rage vortex that is Twitter. It’s hosted across thousands of community-run servers that federate together and has fantastic privacy controls. I can legitimately say, “I love tooting” with a (mostly) straight face. What’s not to like? Nick Peers As you can see from my tutorial this issue, open source has enabled me to escape the tyranny of an expensive, proprietary multi-room audio system. The scope and potential of Logitech Media…

Tesla uses open source software for its autonomous cars, but it’s been getting flak for not sharing its code. Now the company is meeting its open source obligations, posting the source code for its Model S and X cars on GitHub (see https://github.com/teslamotors/linux). This repository includes the system image for the Tesla Autopilot platform, as well as code for its infotainment system, which is powered by Nvidia Tegra. Tesla has also promised that the open source code for its other cars will follow. The move follows efforts from the Software Freedom Conservancy (https://sfconservancy.org), which has been working to get Tesla to release its code in compliance with the GNU General Public Licence version 2. According to the SFC, “We advised Tesla that we had received multiple reports of a GPL…

“After Montreal, Canada in 2017, the Debian Project’s annual conference (DebConf) heads to Hsinchu City, Taiwan. Taking place from 29 July to 5 August, it’ll be the first DebConf to be held in Asia. Debian was established in August 1993 by then-student Ian Murdock, and is one of the oldest and most influential GNU/Linux distributions. Available in 70 spoken languages, the community-driven, fully Open Source distribution currently boasts over 2,000 Debian Developers and contributors combined, and close to one million reported bugs. Whether you’re a developer, contributor or simply interested in learning more about the Debian Project, this year’s edition of DebConf promises to be jam-packed with a bounty of talks, discussion sessions, BoFs, workshops and more. Talks are going to be recorded and live streamed, and will be made…

Linus Torvalds announced the release of Linux 4.17 in a message that can be read at http://bit.ly/linux-new-kernel, observing that, “I didn’t call it 5.0, even though all the git object count numerology was in place for that. It will happen in the not-too distant future, and I’m told all the release scripts on kernel.org are ready for it, but I didn’t feel there was any real reason for it.” However, Linus hints that the move to 5.0 may come around the release of 4.20, “which is when I run out of fingers and toes to keep track of minor releases, and thus starts getting mightily confused.” On a more serious note, 4.17 is actually a smaller kernel than 4.16 because of the removal of dead architectures. There’s also plenty of…

HACK MORECAMBE The coastal town plays host to a week of open experiments to establish a creative platform and group in the area. Starting on 8 September, the week-long event looks at virtual reality, design, blockchain and IoT. They’ll be makers, hackers, artists and open data working hand in hand to use technology for social and environmental good. More details at http://hackmorecambe.com. LINUX PLUMBERS CONFERENCE The “plumbing layer” - that mysterious layer that wraps the kernel and covers utilities such as udev, D-Bus and bootstrap - has its own conference for plumbers to meet and share ideas, talks and workshops. This year’s event takes place in Vancouver, British Columbia, Canada on 13 to 15 November. So if this is your area of specialism, the conference should be on your radar.…

Q drives I suspect is ready that one to fall of my apart hard . With this in mind, I want to back up my whole system other than photo collections and many OS ISO files. Can someone explain how to do a “but not” instruction listing the exceptions please? I’ve been using Mint for some years, but have never had much joy with its Backup Tool. This time it’s telling me it’s calculating, but doesn’t seem to get anywhere. In the past it’s managed to back up, but made a mess of re-installing. It always works fine for /home, but seems to fall over for other directories. Ken, via the now defunkt forums A This was really Neil Bothwick’s answer (or see Roundup on page 26) but he don’t…

Our primary focus with these tools is assessing the contents of their basic feature set, such as whether they offer essential data safekeeping measures such as file encryption, and avoid redundancy by offering to keep incremental backups. Apart from the above, we’ll test the tools to see if they support remote locations and don’t eat up too many resources, because creating backups does require resources. As always, we’ll also test these tools for the documentation and support each offers. Equally important is the interface, because we don’t want a tool that’s full of features, but leaves users floundering about in menus An ideal back-up tool shouldn’t be difficult to master and put to work, which is why we’ve only chosen graphical tools for this month’s Roundup. This is because, unfortunately,…

All administrative tools must balance the need to provide features without comprising on usability. Even the most basic tool that merely copies files into the destination directory would be preferred, if it makes it easy to schedule backups without taking up too much time. Most of the tools in this Roundup are based on powerful and feature-rich command-line tools such as Rsync and Duplicity. These command-line tools are fairly advanced and most of them enable users to specify additional operations to perform when creating their backups. We’ll test the tools for the ease of use, and the amount of assistance each provides for novice users. We don’t want a tool that inundates users with choices and options. Tools with default options designed to make the process simpler will be rated…

If you want a project that makes it easier to upload to a server, you should consider BackupPC. The cross-platform project features a web-based interface and utilises pooling and compression without severely affecting storage and disk I/O. If you don’t mind working with the command line, Borg Backup supports compression out of the box along with 256-bit AES encryption. Also impressive is its use of deduplication and data chunking, which reduces the amount of space required to store the backups. Another popular command-line tool that support incremental backups is rdiff-backup. For those who prefer a GUI, rdiff-backup-web, although still in alpha, provides a web-based frontend. Advanced users can even try BoxBackup, released under a mixed BSD/GPL license. The client-server application supports encryption, and backups are stored on a server, with…

Over the next few pages, we’ll show you how to host your own services to escape the popular walled garden variety. By default, the servers you host will only be accessible from computers and devices connected to your home network. To access them from the Internet, you’ll either have to get a static IP address from your ISP or use a dynamic DNS service and poke holes in your router’s firewall to enable traffic from the Internet. The smarter way though is to use a tunnelling service such as PageKite. Yet hosting everything on your own hardware isn’t feasible when you consider the effort involved in administering the services. So we’ll replace some web services with other online but decentralised alternatives that keep you in charge of your data. This…

As we mentioned earlier in the feature, rolling your own (we’ll cover this in LXF240) email server is tricky. This isn’t because of a lack of quality open source software to power the entire stack of services. In fact, many of the popular email servers around the world are powered by open source software. Instead, the issues with running your own email server are architectural. Many ISPs wouldn’t permit outgoing traffic over port 25 in their bid to curtail spam. Secondly and for similar reasons, emails from new and untrusted servers are usually flagged as spam and filtered by many email servers and online services. Furthermore, an email server is a collection of various individual server components. Assembling and maintaining one requires considerable more time and effort than, say, a…

Julia Lawall is a researcher at Inria in Paris and a kernel developer. She works on the Coccinelle tool, which is used heavily by the kernel team to help automate code transformations. She’s also involved with the Outreachy internship program for underrepresented groups. Julia’s written code that can make sense of GCC’s notoriously opaque error messages, find relevant commits in unwieldy Git histories and much more. We met Julia at the Linux Foundation’s Open Source Summit in Prague in October 2017, where she gave a talk about porting drivers across kernel versions and the tools that can help with that. Linux Format: Tell us a little bit about your employer, Inria, and what you do there. Julia Lawall: Inria is a French government research organisation that’s devoted to computer science…

I first heard of the Raspberry Pi after seeing David Braben talk about it. I was part of the team organising PyCon UK in 2011 and I was trying to make education a theme within the conference. We thought it’d be fun to invite David so he could tell us about this exciting project. Unfortunately, he couldn’t attend, but he did send me one of the very early alpha boards so delegates had something to play with. I mentioned I had a Raspberry Pi during the start of the conference, and thereafter found myself in the middle of a scrum as people wanted to play with it! In the end I just set it up in one of the conference’s open spaces so anyone could have a go. Within minutes…

In this project we used the Enviro pHAT board as a simple colour detector, but this board is capable of so much more. The Enviro pHAT comes with a BMP280 temperature and humidity sensor that enables us to take accurate readings of the environment, so we could use this board as the basis of experiments. But we also have a magnetometer (compass) useful for detecting magnetic north, and we have an accelerometer which can be used to discern gestures and orientation. The colour sensor we used is also a light level sensor so we can use that sensor to measure the light in a room. We also have an ADS1015. What’s that? Well, the Raspberry Pi GPIO can only work digitally, in that the pins are either on or off.…

The project files are in a tarball that can be downloaded from https://linuxformat.  com/archives?iss=239. The project was also tested with an HC-SR501 Human Infrared Sensor. If a different sensor is used the pin out connection will need to reflect the new device. Visit www.chiark. greenend.org.uk/~sgtatham/ putty/  to download Putty, an open source version of an SSH console application. Get the code pyDetect.py at https://pastebin.com/Ds2a4z4n and the other theater_screen. py file at https://pastebin.com/5Ft1yk6q .…

If you purchased new storage that hasn’t yet been formatted, no problem. Install your hardware, boot your Pi then ssh into it from any Terminal. First, we need to identify the drive: The following steps assume it’s been identified as /dev/sda. If it’s not been formatted it’ll claim to have no partition table – fix that with: Press O followed by N and P to create the primary partition. Press 1 and then allocate it all the space by hitting Enter twice. Finally press W to write the changes to disk. Next, format the partition – we’ve picked FAT32 to avoid permissions issues copying files to the drive later: From here, PiCorePlayer will be able to detect and access the drive; Raspbian Lite users need a couple of extra steps.…

1 Prepare the microSD card Download the latest audio-optimised PiCorePlayer image from https://sites.google.com/site/picoreplayer/home/download. Extract the IMG file, insert your microSD card and open Terminal. Go to the IMG file’s directory and use lsblk to spot your microSD card. Type the following (if your card is identified as /dev/sdb: 2 Adding wireless info Once the image has been written, close Terminal and open Text Editor. Type these four lines, substituting your network information where appropriate. Once done, save the file to the root of the PCP volume as newconfig.cfg. 3 Boot and connect Eject the SD card and transfer it across to your Pi. Power on and wait a few minutes before opening Terminal on your PC and installing an IP scanner: Use sudo arp-scan -l to locate your new Pi’s…

OUR EXPERT Jonni Bidwell was recently bitten by a vampire horsefly. During the ensuing delirium, he envisioned a nightmarish future of Linux journalism, in which articles were decided by cryptocurrency auctions. Best not to ask… Nextcloud, the open source, self-hosted platform for storage, sharing and communications, complements this issue’s theme on escaping proprietary cloud services nicely, almost in a manner that suggests we planned it. Nextcloud (an open source fork of Owncloud, which we last covered in LXF213) can comfortably replace Dropbox or Google Drive, but it can do much more, too. In particular, thanks to integration with Collabora Online, it can host and display documents and spreadsheets, creating a free, self-hosted Office solution. Nextcloud can be run on a home or remote server – the installation project is the…

APSO enables you to load external Python scripts with tools that resemble those for LibreOffice Basic. You can learn more about its import library for the language and download the extension itself from https://bit.ly/2s2MArf1  . If you find the icons in these screenshots appealing you can install them yourself from the “libreofficestyle-sifr” package in your Linux distro’s package manager. The ‘Sifr’ or ‘Sifr Dark’ icon styles can then be enabled by selecting Tools>Options >View. You can load the Basic editor more quickly by heading to Tools>Macros> Edit Macros. Alternatively tapping Alt+F11 will load the Macro organiser that’s covered later in this tutorial.…

OUR EXPERT Neil Mohr thinks ‘expert’ is a bit of a stretch of the imagination, but he’s been shirking tech writing for over 20 years. . Virtualisation is almost as old as our beloved integrated silicon chips. At the beginning of the 1960s, there had been two major computing issues. First, many individual mainframe models were bespoke, so incompatible. The other stumbling block was that as integrated processors became more powerful, institutions wanted to implement flexible “timesharing” between multiple users. IBM dismissed this multi-user fad – batch processing was definitely the future! But in 1963, it lost a large MIT contract to General Electric. Realising its huge mistake, IBM developed the general-purpose S/360 architecture, which could be implemented on a wide range of compatible systems. In 1965, IBM released the…

The Random Forest classifier is one many ensemble methods of creating machine-learning models in the sklearn package. While deep learning gets a lot of attention these days, there are other methods that perform well enough for many other applications. Random Forests work by training a number of decisions trees with the training data so that the resulting ‘forest’ accurately reflects how the features (in our case, words) translate into classifications (in our case, positive and negative). You can visualise this as a space that’s divided up by a complex tree, which branches off one way or another – positive or negative – depending on the training data (the words and labels). If you’re interested in machine learning, it’s worth looking at classifiers outside deep learning, since these still have a…

I installed LineageOS 15.1 (Android 8.1 Oreo) on my “aging” OnePlus Two recently. It’s running beautifully - better than ever I’d say, with improved battery life and bang up-to-date security and support updates. Without the freed open source world that simply wouldn’t be possible and I’d be stuck on the last update OnePlus released for the Two, back in November 2017… a mere two years after its original production. That’s just one of the many points to open source. Highly skilled, knowledgeable people with the right motivation can achieve wonders by working together. It enables us to pack this magazine every month with fabulous projects and features. It’s also partly what drove Microsoft to buy GitHub – we cover this in more depth in our news on page 6 –…

It’s been a rough year so far when it comes to security vulnerabilities, and two recent disclosures mean the bad news keeps on coming. First of all, security researchers revealed vulnerabilities in secure email applications, which enables malicious users to intercept and decrypt PGP-encrypted messages. Known as EFAIL (https://efail.de), these vulnerabilities affect emails made with OpenPGP and S/MIMIE, leaking the plain text of encrypted emails. According to the EFAIL website, the vulnerabilities rely on the active content of HTML emails (such as images loaded from an external source), which have been intercepted by gaining access to network traffic, or from compromised email accounts. The attacker changes an encrypted email and sends this altered encrypted email to the victim. The victim’s email client decrypts the email and loads any external content,…

Valve has officially launched its Steam Link Android app on the Google Play store (http://bit.ly/steam-link-app).The app enables you to stream games installed through Steam on your desktop PC to an Android device. You can then use a controller – such as Valve’s Steam Controller – to control the game. We’ve had a play around with the app and can confirm that it works very well, and it operates with Steam installed on a Linux machine. As long as you have a pretty decent wireless network, then you shouldn’t encounter too much lag when playing. It’s a great way of getting desktop games onto an Android device, although of course you need your desktop PC to be turned on and running Steam to work. It also works with Android TV devices,…

DEVUAN GNU+LINUX 2.0.0 A new, stable version of the Debian fork that offers a Systemd-free alternative is now available to download. Based on Debian 9.0, it’s available for a wide range of platforms, including standard desktops and live installs, as well as SoCs such as the Raspberry Pi. You’re provided with a choice of desktop environments such as Xfce, KDE, MATE and Cinnamon. The release notes can be viewed at https://bit.ly/2Mg9rZy, which explains the thinking behind this new release. GECKOLINUX 150 If you’re looking for a user-friendly version of openSUSE that can play a range of media codecs, then you may be interested in this new release. Based on openSUSE’s stable Leap edition, there are several desktop spins and a BareBones minimal spin of the stable edition, as well as…

Last orders at the Bar(camp)? Don’t let this maker meet-up format fade away. Back in 2009 we attended Barcamp Blackpool and Oggcamp. Both of these events had something in common: they followed the barcamp/ unconference model. This is the opposite of a planned conference. Unconferences offer the attendees the facilities to host a talk on their own interests and projects. In the late 2000s the number of barcamps/ unconferences was growing and with it the early days of the current maker culture. But in recent years the number of UK-based unconference events has dropped, and for some remaining events the number of attendees has fallen. These events are important because such grass-roots events are where the most interesting projects are created. Free from external influences, unconferences can generate successful projects…

Live wire Q I have been an on-off user of Linux for many years. I was initially tempted by the magic of Knoppix 3, then I succumbed to the power of openSUSE 10 and enjoyed the fun of Puppy 5. More recently I’ve discovered MX Linux 18, which seems to work flawlessly on every single PC and laptop I boot. I have tried many distros over the years (mainly from live images), but always come back to Knoppix, which is now at version 8. I must add that I’m still very much a novice Linux user. I use Knoppix all the time now. It has become my day-to-day working desktop. I save my changes to a persistent data file that gets saved on exit and loaded on boot. It’s so…

We’d love to try and answer any questions you send to lxf.answers@futurenet.com, no matter what the level. We’ve all been stuck before, so don’t be shy. However, we’re only human (although many suspect Jonni is a robot), so it’s important that you include as much information as you can. If something works on one distro but not another, then tell us. If you get an error message, please tell us the exact message and precisely what you did to invoke it. If you have, or suspect, a hardware problem, let us know about the hardware. Consider installing hardinfo or lshw. These programs list the hardware on your machine, so send us their output. If you’re unwilling, or unable, to install these, run the following commands in a root terminal and…

Here’s a classic example of a modern NAS device. It’s designed to be purchased for a specific job, but then can be repurposed repeatedly over its working life. Can this new series of ReadyNAS hardware take on Synology in that slice of the market where it is strongest? The RN422 is over-engineered to the point that it feels heavy even before drives are mounted. The look that Netgear is pitching with the new ReadyNAS series is a minimalist one with a twist of functionality. The fascia is hinged on the left and opens to reveal the two internal drive bays that enable either 2.5- or 3.5-inch drives to be quickly mounted. The larger drives don’t require any tools to install, but you will need a screwdriver for 2.5-inch hard drives…

Since some of these tools are developed by a single developer or only a small team of developers, they don’t provide more than a source tarball, or a Git repository. So it’s left to the contributors and developers working with popular distributions like Fedora, Debian and Ubuntu to package these tools for their distributions. Sadly, the latest version of most of these tools isn’t available in the software repositories of most distributions. However, https://pkgs.org is a good resource if you’re looking for installable binaries for these tools. While DejaDup is featured in the software repositories for most distributions, with the exception of Fedora, all others feature a much older version in their repositories. The Fedora repositories are also home to the latest version of all the other tools. The only…

he one truly surprising part of the T Information Age is the extent to which our personal information, has been commercialised. Edward Snowden’s warnings were played down as fear mongering by a privacy paranoid traitor. But recent events have shown that companies will go to any extent to collect and use our data for everything from swaying our shopping habits to influencing democracies. We’re being tricked into handing over tons of data, usually in the garb of convenience, to the many online services we use everyday on our laptops and smartphones. From the ubiquitous cookies to single-sign ons and social buttons, there’s an unending array of data accumulating technology that follows us all over the web. Thanks to an arsenal of such tools, the online behemoths like Google, Facebook and…

LXF: Can you tell us a little bit about the Outreachy program and your involvement with it? JL: Outreachy is an internship program for women over 18. It pairs them with a mentor, and then they work on an open source project. So it’s a sort of hierarchical thing: there’s administration, then there’s each organisation and so I’m the coordinator for the Linux Kernel. I find mentors for each round – there are two rounds each year – then there’s an application period and then the mentors pick which intern they would like, then the interns do their internship for three months. I got involved with it because I work on Coccinelle – a tool that enables people to write rules. You can write a kind of pattern, then that…

Ubuntu’s efforts to do things its own way regularly attracts criticism: Mir was seen as diverting developer attention from Wayland, or a solution to a problem that didn’t exist. And many Linux Mint users were once Ubuntu users who fled when Unity came along. But Upstart, Canonical’s asynchronous, event-based init system, was generally well-regarded and saw widespread adoption. Besides Ubuntu (until 14.10), Fedora (from 9 to 14) and RHEL6, Upstart was used by Nokia’s Maemo and Palm webOS (which lives on in LG TVs). It’s still used in Chrome OS and Chromium OS too. It was designed to be backwards compatible with sysvinit scripts, flexible and simple. Services could be simply controlled using SysV compatible commands, for example sudo service sshd start and the syntax for writing job files was…

OUR EXPERT Sean D. Conway With 35 years of extensive IT experience under his belt, this tech expert is on the verge of well-deserved retirement. The goal of this project is to create an animated background for a self-contained diorama within a large model train layout. In short, we’ll be simulating the iconic screen of a drive-in cinema, which adds movement and brings the scene to life. The Walthers Skyview Drive-In Theater model kit is designed to hold a seven-inch screen such as a tablet, but it can be achieved just as well with a Raspberry Pi and a standalone touchscreen. A motion sensor will bring the projection screen to life whenever someone approaches the diorama. The Pi mounted to a LCD will replace the static cardboard screen cut-outs that…

Many electronic enthusiasts know that the operation of electronic devices is all smoke and mirrors. The British science fiction writer and futurist Arthur C Clarke is credited with saying, “Any sufficiently advanced technology is indistinguishable from magic.” Why smoke and mirrors, you ask? When your actions cause electronic devices to smoke by hooking them up incorrectly, it’s the components that are actually giving off smoke – and then don’t work anymore. This cause/effect understanding leads you to the understanding that the device operates on smoke. When tinkering with electronic it’s extremely important to keep the smoke in the devices. This reduces the cost of projects as well as getting you one step closer to working. If your actions result in a device releasing its magic smoke, then the device will…

PiCorePlayer’s extensive help files can be accessed via http://picoreplayer. sourceforge.net/main_about. shtml  – you’ll find all the detailed information you need to get up and running. From time to time you’ll be informed that a new version of LMS has been released. PiCorePlayer users can install this through the LMS tab on the main PCP interface by clicking ‘LMS Update’; Raspbian users will be told a new version has been downloaded. Follow the instructions to update it from the command line. Ensure your music library is tagged with the correct metadata. Simplify the task by using your main PC and a tool like EasyTAG to get metadata from online servers and integrate it into your tracks, plus embed artwork into the files.…

OUR EXPERT Shashank Sharma is as fond of Gnome desktop as he is of Bash, and is loathed to work with alternatives. An avid Arch user, he spends his days as a trial lawyer in Delhi.. Atypical Linux distribution ships with a vast number of command-line tools and utilities out of the box, which can be used to perform routine tasks such as listing directories, working with text files, or performing basic copy, move and rename operations. You can also find more specialist and esoteric tools designed for specific tasks, such as for working with databases, browsing the web, downloading files and so on. Some tools, like grep, through sheer usefulness, have become an important part of the CLI users’ everyday arsenal. If you’re interested in working with the terminal,…

Dynamic DNS and SSL Certificates are simple to set up, we just can’t fit the instructions into this box. But you’ll find guides at https://duckdns.org  and https://letsencrypt.org. There are no issues getting the latter to sign a certificate for a domain provided by the former. Besides CODE, there are all kinds of other applications that can connect with Nextcloud. The popular Rainloop, for example, can integrate your email (whether self-hosted or via another provider such as Gmail) into the Nextcloud interface.…

OUR EXPERT Bobby Moss creates online documentation for enterprise virtualisation and Linux products. In his spare time he works on a range of free software projects.. Over the past year this industrious writer has covered how to get the most out of LibreOffice applications like Calc, Base and Impress. But what if we said that you could extend your experience still further? Don’t worry, we’re not about to have a spectacular failure of imagination and regale you with a tutorial on Draw like a sneaky teenager did back in LXF139. This issue we’ll help you explore how to expand the functionality of Calc and Writer in ways the LibreOffice devs never planned for, and all in a way that doesn’t require you to take a programming course or lose a…

One of the main benefits of coding in Basic is you can see exactly what will happen when you run your code from start to finish. But even with this simplicity it can get a little confusing as the amount of code increases and mistakes (or “bugs”) start to creep in to your macro’s instructions. In this situation it can be helpful to break down your code into smaller, more testable components such as functions, with output you can reasonably predict from existing input. In the world of professional software development we would use “unit tests” to verify that inputting certain values into a function returns the value or outcome that we expect. Unfortunately, we don’t have the luxury of a testing framework, but LibreOffice Basic still has useful debugging…

OUR EXPERT Stuart Burns is a Fortune 500 virtualisation expert by day and Linux nerd by the weekend. He enjoys fiddling with all things Linux, especially when virtualised.. Linux users will often be given older laptops, just because they like computers ‘n’ stuff. Which is fine – better than letting such laptops sit around gathering dust. This article looks at configuring those relatively modern Dell laptops to obtain the optimum Linux experience. We’ll be using a Dell XPS 13-inch laptop for this project. To make the experience as seamless as possible we’ll provide a few tips that will save you both time and frustration later on. It’s assumed that the laptop in question has Windows installed on it. This tutorial also assumes that UEFI (Unified Extensible Firmware Interface) has been…

For x86 processors there are a number of different hardware features that have been added over time to help accelerate virtualisation of guests. It’s worth covering these, because they offer an insight into the work the virtual host is having to do. Virtualisation software largely has two options when it comes to running guest software faster: full virtualisation or paravirtualisation. The full option, as you might guess, requires the host to recreate every aspect of the virtualised hardware, from the full instruction set, I/O operations/devices, interrupts and memory. For x86 code running on an x86 machine, instructions can largely be run directly, but any instructions or I/O access that violate the virtual machine have to be trapped and translated – this slows everything down. To help speed up virtualisation, AMD…

Version: 0.13 Web: http://lxqt.org We often say that freedom of choice is the cornerstone of open source software, and it’s particularly true when it comes to choosing a lightweight desktop environment. This month’s leading HotPick is for those Linux Format readers who own a low-end computer or just don’t want to waste their computing power on unnecessary visual fripperies. LxQt is a decent alternative to the traditional standoff between Plasma and Gnome, but we strongly believe that LxQt has the potential to lure away some MATE users as well. The secret to its success doesn’t lie solely in its speed and lightweight nature, as you might expect, but rather in the fact that LxQt also maintains great UI consistency. That helps it to build a neat and pro-looking desktop of…

Important point: this author tied himself in knots trying to install the required packages. If you can, make sure that you’re running the latest version of Raspbian (which was ‘Stretch’ in this case) and make sure that you’re installing pip packages from piwheel instead of the default Python wheel. Piwheel has packages that have been pre-compiled for the Raspberry Pi’s architecture and without this the pip will try to compile, which won’t often work easily. An excellent description of this is available in Ben Nuttall’s post: http://bennuttall.com/piwheels-building-a-faster-python-packagerepository-for-raspberry-pi-users Once you’ve got everything set up, you’ll want more data to play with. Getting good training data can be a chore that has distracted many people from getting anywhere with their machine-learning skills. Instead of tying yourself up in knots over this, go…

“THIS IS PRETTY GOOD NEWS FOR THE WORLD OF OPEN SOURCE AND WE SHOULD CELEBRATE MICROSOFT’S SMART MOVE” Microsoft has acquired GitHub for $7.5 billion in Microsoft stock, and while that headline may have been shocking a few years ago, there was plenty of speculation and rumour concerning the potential buyout in the weeks leading up to the announcement. With GitHub hosting the largest collection of code in the world, it’s certainly big news, even if it’s not that surprising. As of March 2018, GitHub claimed there were 28 million developers in its community, and 85 million code repositories, and with Microsoft’s renewed focus on software and services, many people expected this move. As Satya Nadella, the CEO of Microsoft, explains in a blog post (http://bit.ly/micro-github1 ), “developers will be…

“The seventh annual Open Source Jobs Report from The Linux Foundation and Dice has been released, and it’s revealed that demand for open source talent is as strong as ever. Among its findings, 89 per cent of hiring managers reported difficulty in finding skilled open source workers. While 48 per cent of managers report their companies have begun to support open source projects with code or other resources, just to recruit individuals with skills in that software. Linux is the most sought-after skill with 80 per cent of hiring managers looking for tech professionals with Linux know-how. And 55 per cent of employers are offering to pay for employees certifications, “There’s a gulf between the views of hiring managers and open source pros on the effectiveness of efforts to improve…

A Over 10,000 students in Swiss schools will soon be using largely open source software, with Bern, the capital of Switzerland, signing the largest open source contract in Switzerland. It will see public schools use a package of open source applications, including Colabora Cloud Office, Nextcloud, Kolab, Moodle and Mahara. The contract is thought to be worth CHF 13.7 million over the next six years. However, as TechDriveIn reports (http://bit.ly/bernsoftware), the software will be run on Apple’s proprietary iOS platform, as the students will be all given iPads. There’s probably cheaper ways to do that, but hey, it’s a good start.…

“Which open source projects have your name (or your company’s name) listed as a contributor? If the answer is “none”, let’s append a “yet” to that. Pretty much by definition, all readers of Linux Format use open source software on a daily basis, and most businesses do, too. If not overtly running Linux somewhere, they have an Apache website, or use Firefox or Thunderbird, and so on. The call for contributions isn’t new, but let’s exclude bug reporting. Yes, that’s useful, but it passes the workload to someone else. Instead, let’s actually do the work. If you can’t code, that’s fine: maybe you can improve the documentation, design a logo, or – and the scope is pretty huge here – improve an open source project website. If your employer uses…

Alpinux, le LUG de Savoie Meets on the first and third Thursday of the month at the Maison des Associations de Chambéry, France www.alpinux.org Build Brighton Thursday evenings is open night. www.buildbrighton.com Sandbox Sandbox Digital, 5 Brasenose Road, Liverpool L20 8HL. Open maker night is Tuesday 6-9. Kids clubs are Monday (six to eight years) and Wednesday (eight to 12 years). www.sandboxdigital.co.uk Leeds Hackspace Open night every Tuesday 7pm-late, open day second Saturday of the month, 11am-4pm. www.leedshackspace.org.uk Horsham Raspberry Jam Park side, Chart Way, Horsham. www.facebook.com/hackhorsham rLab Reading Hackspace Unit C1, Weldale Street, Reading. Wednesdays from 7pm. http://rlab.org.uk Huddersfield Raspberry Jam Meet every month at Huddersfield Library, typically the fourth Saturday of each month. www.huddersfieldraspberryjam.co.uk Medway Makers 12 Dunlin Drive, St Mary’s Island, Chatham, ME2 3JE. www.medwaymakers.com Cornwall Tech…

Q USB Micro memory SD cards sticks are great and SD . / However, when memory media are formatted using FAT on a Linux system using gnome-disks or gparted they become unusable, and prohibit writing to the drive. This requires opening the terminal and executing chmod and chown. This makes the use of a simple – albeit unsecure – system very difficult. Is there a GUI formatting program that creates a usable USB stick? Or can you run a article explaining the reasons for the unusability of this media, with a simple recipe to create insecure, usable USB sticks. Cheers! Basil Orr, via email A Hi Basil, FAT filesystems have no security. Permissions are assigned based on who (or what) mounts them. So if you mount it from the terminal…

The OnePlus 6 is the most polished, premium smartphone the firm has made in its short existence. It boasts an all-glass design, bringing it in line with big-name flagships such as the Samsung Galaxy S9 and iPhone X, a large 6.28-inch display complete with the on-trend notch, dual rear-facing cameras, both fingerprint and face unlock, and up to 256GB of storage. The display is one of the big new features on the phone. In fact, it’s the biggest display the firm has ever produced, with the 6.28-inch Full Optic AMOLED panel eclipsing the 6.1-inch offering found on the 5T. The resolution stays the same at ‘just’ Full HD. That’s 2,280 x 1,080 to be exact, which ensures it keeps the 402 pixels-per-inch density of previous OnePlus flagships. However, in a…

Properly used, back-up tools can help safeguard your data against disk failure, or any kind of corruption or attack. Over the next few pages we’ll test some of the popular desktop back-up tools which you can use to back up all your sensitive directories and configuration files. The right tool will not only back up your data, but do so securely. To save on disk space, some of these tools also offer to make incremental backups. Although a vast number of solutions are available, we’ve chosen to focus exclusively on graphical tools for this Roundup. Since last we looked at back-up tools, way back in LXF207, a lot of tools that were popular at the time have shut up shop. More importantly, two of the tools features in this Roundup,…

The decision whether to use encryption on your backups depends largely on the type of data being backed up. Similarly, whether to use compression would depend on a number of factors, including the destination for your backups. You would want to use compression if you plan on hosting backups on a remote location on the network, or even the cloud. Since last we looked at it, luckyBackup has ceased active development, which means that although the latest release is still supported, the developer isn’t working on adding new features. Although the project had planned to add support for creating compressed and encrypted backups, that’s no longer the case. While it doesn’t support compression, you can create local encrypted backups with Back In Time. The tool users EncFS to safeguard your…

1 Create a new library Log into the administration interface and click the New Library button. You’ll have to then specify the name of the library you wish to create. For added security you can optionally toggle the Encrypt checkbox and then specify a password to conceal the contents with AES 256. Remember that while a library can have any number of folders, you can only create libraries under the root directory of the server. 2 Upload your files After you have created a library, it’ll be listed under the My Libraries section. Click the name of the library to access its contents. You can now use the Upload button to either upload files or entire folders from your computer to this share. There’s also the New button that offers…

The UK’s Scout Association and the Raspberry Pi Foundation have teamed up to create a series of Digital Maker badges that young people can work towards and achieve. The Digital Maker Staged Activity badge will help young people to develop skills in problem solving, resilience and creativity, alongside key digital skills that are essential for today’s school work and tomorrow’s adult life and career possibilities. The activities have been designed to be accessible and relevant to scouts. Indeed, you don’t even need a Pi to meet the requirements: tasks can be accomplished on a standard laptop without the need for internet access. They’re based around completing tasks in Scratch and involve creating a digital compass, digital art and more. Visit https://fundraising.scouts.org.uk/raspberrypi for details.…

OUR EXPERT Les Pounder is a freelance maker who works with organisations such as the Raspberry Pi Foundation to promote maker skills. Read his blog at bigl.es. The Raspberry Pi has many add-on boards, and the nature of the GPIO pins means that only one board can be used at any one time. However, a breakout board enables you to duplicate the GPIO pins and run two add-on boards at once. In this project we shall use two add-on boards from Pimoroni. The Enviro pHAT is a sensor platform that can measure light levels, compass heading, temperature, air pressure, colour and movement. We also have the Unicorn pHAT, which is an array of 32 neopixels (individually controllable multi-colour LEDs). So using these boards we shall create a colour catcher, a…

The rainbow screen appears on every boot, to test the graphics processing unit (GPU). If the Pi fails to boot and you didn’t see the screen, it could suggest that the kernel.img file isn’t available. This could indicate there’s an issue with the image on your SD card. The missing rainbow screen could also mean that your power supply isn’t powerful enough. The amount of current demanded from Pi power supplies increased as new versions of the board were introduced. Adding external devices that rely on the Pi power supply, such as the sensor, also increases current demand. If a rainbow-coloured cube is displayed in the corner of your screen it means your power supply is under-voltage. If the rainbow is red, there’s an overheating issue. Your Raspberry Pi might…

OUR EXPERT Nick Peers had his mind blown when he embarked on this project. Now his family – and the neighbours – must endure his questionable musical tastes throughout the house. At least the sound quality’s decent.. The dream of every audiophile is the ability to listen to music on demand in any room in your home without having to cart CDs, speakers or headphones with you. Manufacturers like Bose and Sonos deliver this dream, but at a price that’s prohibitive to most. Our mission, therefore, was to deliver a Sonos-like experience for a fraction of the cost, and thanks to the Raspberry Pi and generosity of Logitech, it’s mission accomplished. Over the next two issues we’re going to reveal how to build your own multi-room audio system around a…

You’re throwing a party and you’d like everyone in the house to hear the same soundtrack. Thankfully, pairing your players together so the same music is heard on multiple speakers at once is child’s play in LMS. It’s done by organising players into groups, which can be done on ad-hoc basis or as a permanent setting. The quickest way to sync your players is via the player drop-down menu in the top right-hand corner of the LMSweb interface. Use it to select your first player, then click the menu again and choose Synchronize… to select the player you want to sync this one with – the second player’s Now Playing list will be selected by default. Now select your third player before choosing Synchronization again and choosing your paired group.…

You can even use regular expressions when performing pattern matching with grep. The command supports all the usual wildcards such as ., *, ^, $ and ?. Square brackets provide an additional level of control over search parameters and enable you to define class of matches. For instance, if you want to find all lines that begin with lower case alphabet, which is a grammatical abomination, you can do that with the grep “^[a-z]” <filename> command. The full extent of what’s possible with brackets is beyond the scope of this tutorial, but you will find various online resources discussing different possibilities. For the OR operation, you can use pipe ( | ) with the -E command option. The grep -E “pattern|string” filename command will display lines that contain either the…

Collabora has just released the latest version of its enterprise edition of LibreOffice: Collabora Office 6.0 (see www.collaboraoffice.com/collabora-office-6-0). Collabora Office powers another application, Collabora Online, which provides an online version of the office suite, that can be plugged into a file sync and share host via the Web Application Open Platform Interface (WOPI). A free version of Collabora Online – the Development Edition, aimed at home users – is available, and it can be connected to your Nextcloud instance to provide functionality not dissimilar to Google Docs. The easiest way to set it up is to use the Docker image and follow the instructions at https://nextcloud.com/collaboraonline. The CODE docker image listens on localhost:9980, so for this to be accessible to the outside world the instructions use an Apache reverse proxy.…

There are two types of variable in LibreOffice Basic. Global variables are defined inside a module file and can be used by any subroutine or function within it. Local variables can only be used within the subroutine or function it’s declared inside. By convention people typically use Dim for variables they want to declare a type for, like so: A common mistake new programmers sometimes make is getting confused about the difference between subroutines and functions. Both will accept parameters (variables that you provide as inputs), perform operations in a predetermined order and change the value of global variables. The key difference is that a function will output a value for use in a variable, while a subroutine doesn’t need to. In the example below you can see a function…

Recording macros and coding things in Basic and Python isn’t the only way to extend functionality in LibreOffice. In LXF142 we dedicated plenty of space to OpenOffice.org plug-ins, so it seems only fitting to do the same this issue. You can find a full listing of supported extensions and templates at https://extensions.libreoffice.org. One plug-in that caught our eye that never sleeps was Power Detective. With larger datasets with a lot of different calculations it can be tricky to determine how one change might affect other parts of the sheet. This plugin draws arrows from any given cell to any other cells that are dependent on it to complete their functions, ensuring you don’t accidentally miss any parts of the sheet with “#REF!” as their value before sharing it. Another example…

While talking to Dell, one of the main things to come out was the fact that it’s vital to pay attention to the BIOS settings. Not only should you ensure that the installed BIOS is running the latest available version of the BIOS, but there are also a number of configuration items that need to be addressed for it to work as expected. Within the BIOS settings, due to what can only be described as “issues”, Dell recommends that the Intel RST NVMe (Intel Rapid Storage Technology that’s used in modern solid state disks) setting is set to “off”. If there are issues encountered that are suspected to be BIOS related, there’s no reason not to do a full reset to factory default so that it’s “known good”. Just remember…

Really, these are two sides of the same coin. Emulation is used to describe full-system virtualisation, which also includes the guest’s processor and all hardware. A VM created in VirtualBox will largely be using the same hardware (para-virtualisation) as the host, so a lot of optimisations can be made that way. Usually with an emulator, the processor, graphics and custom hardware controllers all have to be trapped and remapped to IBM-PC hardware. Virtualisation can also be done in different ways. You might have noticed (or possibly not) that Microsoft has been sucking up to Linux more and more in recent years. Not only is Microsoft using open source and Linux system internally (and admitting it) – it’s offering Linux in its own store, so you can run it on Windows…

OUR EXPERT Dan Frost leads R&D projects in edtech, writes and podcasts about emerging tech and business at blog. thebaseline.co. Sentiment analysis is the use of algorithms or machine-learning models to identify the likely mood or feeling in a given piece of text. This can be as crude as spotting good words such as “like” and “awesome” and bad words such as “rubbish” and “poor”. Or it can be as complex as taking into account the apparent meaning of each words in the wider context, such as the word “crushing” which can be bad (feeling) or good (“crushing it”). This can give your system a somewhat human behaviour of responding with “that’s great” or “sorry to hear that”. It’s been used to for predicting the stock market by looking at…