Sommaire pour November 2015 de Linux Format

Jonni Bidwell I’ve been playing a lot of Transistor lately. It’s a sci-fi action roleplay game with a great story, superb graphics and it’s a whole lot of fun to play. And it works on Linux. That, together my penchant for psytrance music, keep me pretty much entertained as the dark nights draw in. Neil Bothwick I think the most enjoyable part of using Linux is the ability to be able to fiddle and tweak everything to my heart’s content. Then one of the least enjoyable parts is trying to work out what I have broken with my excessive fiddling and tweaking and what I need to do to fix it. Les Pounder HD movies and TV series box sets are great but there’s something really geeky about watching Star…

When CEO Satya Nadella announced that “Microsoft loves Linux”, his statement was met with shock as well as a hefty dose of cynicism. Sure, the Redmond company’s much touted Azure cloud service mainly runs on Linux, but has it really changed its ways and dropped its, at times, openly hostile attitude to Linux? Sadly, despite all the positive PR, which at least succeeded in giving Microsoft and its Azure platform plenty of coverage, Microsoft may not be quite as open with Linux as it claims. An impassioned article on the TechRights website (which can be read at http://bit.ly/MSLovesLinuxBaloney), claims that Microsoft is still up to its old patent-trolling tricks. Though it’s not outright patent trolling, the article alleges that Microsoft, through a shell company with a patent linked to Intellectual…

“This has been a month of frantic activity for the free software office suites. First, we had an Open Document Format (ODF) plug-fest at The Hague hosted by the Netherlands Ministry of the Interior, who announced stronger enforcement of its recommendations to use ODF. Microsoft announced that it will support ODF 1.2 on all its mobile & other non-desktop Office apps, and the UK government presented its best-practices for ODF usage. The technical part of the plug-fest extended the growing suite of automatic interoperability tests, and a number of fixes were made there and then to implementations. A couple of weeks later was the LibreOffice conference in Aarhus, with several notable highlights. Continuing the ODF thread, it was great to see the Taiwanese government inspired by the UK’s example to…

So here it is. Another release of Windows and, as expected, LXF201’s lead story is another marketing exercise to say how far behind Windows is from Linux. It’s got translucency? PAH! Linux had that years ago. It supports older hardware? PAP! Linux has done for years… What are you going to do now Windows is a rolling free update? Run something annually? Come on! We buy LXF because we like Linux and know it is far better than the ‘beast from Redmond. Do you really need all those pages dedicated to something we already appreciate? There is so much more in the Linux world that you could cover. Yes, certainly report that a rival has updated its offering, though when iOS gets an upgrade there isn’t the same level of…

Preston Hackspace This popular hackspace has secured a meeting room at UCLAN, Preston and has support from Ultimaker for its 3D printer. Jayd Lawrence and Ben Horn are determined to create a welcoming and creative space in Preston. At each session there are a plethora of hacks on offer: from Arduino and Raspberry Pi-based hacks to drone projects. http://prestonhackspace.org.uk Scale14x The 14th Southern California Linux Expo takes place on 21-24 January 2016 at the Pasadena Convention Centre. Four days of Linux and open source tutorials, workshops and exhibitors all showcasing the latest products and projects in the community. Sponsored by big names such as HP and O’Reilly, this is the first major FOSS event of 2016 and historically draws a big crowd. More info is on the website. www.socallinuxexpo.org UK…

File sychronisation software doesn’t have the vast array choice that you will find for the likes of media players or text editors, where there are almost enough choices for each user to have something different and tailored to their needs. There are, however, a few other file synchronisation programs available for desktop use, such as csync (http://csync.org), which didn’t quite make our list but is worthy of a look. This is a client-only bi-directionational file sychroniser, which is intended to provide ‘roaming directories’ for syncing anything a ‘normal user’ would want, such as media collections and backups. There are also a multitude of mobile utilities that connect to your home computer, if your main concern is keeping your phone and computer in sync, eg for Android, we’ve used FolderSyncand Titanium…

The quad-core Raspberry Pi 2 is powerful enough to run a decent media server – albeit with some restrictions, chiefly that it’s not powerful enough to transcode between formats, so it will work best if your media is in a format compatible with the devices you plan to run it on. In most cases, using MP4 video with H.264/ MP3 codecs plus MP3 music files will fit the bill. The Pi 2 can perform limited transcoding when prepping a file for streaming, meaning that you should be able to access your media even outside your local network, but expect significant delays – over a minute – while the transcoding takes place. You’ll also notice some lags when accessing the server, but it’s not too bad; we’ve happily run a Pi…

Microsoft builds itself a Linux-based system Reporters scramble to check for flying pigs and evidence of hell freezing over, while elsewhere a mysterious hacker patches routers. We experienced a move recently which would have seemed utterly unthinkable just a few years ago, Microsoft revealed in a blog posting for its Azure cloud platform that it had developed its very own Linux based distro. Before we all get too carried away about whether Microsoft prefers KDE or Gnome though we should point out that in this case, Linux is being used as the base for something called the Azure Cloud Switch. This is Microsoft venturing into writing software for network devices. Due to its flexibility, Linux excels at this kind of scenario and is a common sight in network cabinets. Details…

A ‘Canary deployment’ is the idea that a version of an application can be rolled out to sit alongside a live production service and receive production traffic. If its not obvious, the canary reference is a nod to the old practice of having caged birds in mines to give an early warning of the presence of harmful gas. Should the bird/ new version of the app keel over with its legs stuck up in the air, a miner/deployment team will know that something is amiss and get the hell out. By using labels (see main article), we can easily deploy and discern between different versions of an application and just as easily take them offline again (imagine using a ‘version:1.0’ and ‘version:1.1’ label in this situation). Similarly handy is an…

Our expert Les Pounder is a wandering Pi maestro, who travels the UK dispensing the Way of the Pi on behalf of the benevolent Raspberry Pi Foundation. In his spare time he enjoys hacking stuff and writing about it on http://bigl.es. The Sense HAT is a remarkable platform with sensors covering temperature, humidity and pressure. It also has an accelerometer gyroscope and compass which can be used for positional data. To top it off the board has an 8x8 LED matrix and joystick. In this project we’ll be using this marvellous device to measure temperature, humidity, pressure and to draw animations on that matrix. As well as the Sense HAT, you’ll need either a Raspberry Pi 2, A+ or B+, a copy of Raspbian and an internet connection. All of…

Our expert Mayank Sharma was a contributing editor for www.linux.com and has written for Linux Today, Digg and PC Plus. A printer isn’t the most convenient of peripherals. They look out of place on most work desks and create quite a racket when spitting out pages. You could throw a few hundred quid on a snazzy new network printer that sits in a corner somewhere and can receive print orders from any computer on the local network or you could just hook your regular USB printer to the Raspberry Pi and enjoy the same conveniences offered by top of the line network printers. If you haven’t already used your printer on Linux, before you get started with this project head to www.openprinting.org/printers to check whether your printer is compatible with…

In addition to adding printers, the CUPS web interface provides access to various other useful settings. You can administer most of the printing tasks from the Administration tab, which houses settings under various different categories. Under the Server section, for instance, you can find options to tweak the configuration of the server as well as view various types of access and error logs. Using the ‘Manage Printers’ button under the Printer section, you can control the settings for individual printers. Every printer’s page has options rolled under two pull-down menus labelled Maintenance and Administration. From under the Maintenance menu, you can print a test page, a self-test page, clean print heads and manage print jobs. To customise the behaviour of the printer, use the Administration menu to tweak its default…

Some desktop environments render their wallpaper above the desktop, which requires a little trickery to get it to show through Conky. Even though Conky’s background is transparent, there’s nothing to show through it. You’ll need to Install the feh image viewer, then locate the file used for your wallpaper, now create a short shell script like this: This causes feh to render the same wallpaper on the ‘real’ desktop background. Run this script instead of Conky to start it, and make sure you set background yes in .conkyrc or the script will never reach the feh command.…

Our expert Nick Peers has over 20 years of experience writing for various platforms, and has been dabbling with Linux for the best part of a decade. Desktops Select the right desktop environment that suits your OS needs The desktop environment is a critical aspect of your Linux user experience, providing you with a more user-friendly way to interact with your PC. Unlike Windows or Mac, Linux doesn’t tie you to just one, and as we discovered last month, switching desktops is incredibly straightforward. If you’re struggling with your distro’s default desktop, then it’s time to make a change. But rather than simply experiment with different desktops until you find the one you’re looking for, it pays to form an idea of what you specifically want from a desktop, then…

You’re able to run Arch Linux directly on a dual-boot system, though currently driver issues prevent a graphical interface. Once Developer Mode is on dive into a shell and type sudo su then enable USB booting with: Reboot and we can format, partition and install Arch onto the SD card. This works on USB drives too, just replace mmcblk1 with sda for the USB drive. We need to unmount, format, partition, download, extract, configure and boot Arch, like so. Use unmount mmcblk1 to unmount everything. To create a new GPT partition use fdisk /dev/mmcblk1 and type g and w to create and write the GPT table. To partition it use: To add a root partition we need to calculate its size, use cgpt show /dev/mmcblk1 to list the devices size.…

Our expert Jonni Bidwell is tired of roadways and pavements grey, he dreams of a cabin on the Lake Isle of Innisfree, living alone in the bee-loud glade… We’ve done all kinds of introductory level programming in Linux Format: hacking around with Minecraft, ancient board games in Python, word games in PHP [do all our writers just play games all day? – Ed]. But these tend to be either console-based text only affairs, or dependent on some prefabricated graphical interface, surely it must be possible to make your own? Most of the graphical applications (the ones that run in their own windows at least) you’ll come across on Linux fall into two camps Qt(pronounced ‘cute') and GTK (pronounced… [Oh, get on with it – Ed]). These are the two different…

This month we answer questions on: 1 Distro only booting to the CLI 2 How to downgrade Wine 3 Clonezilla misbehaviour 4 DVD booting errors 5 Partition rearrangement * Adding wallpapers 1 GUI gone Q Each month I tinker with a spare computer and install all the versions of Linux from the LXF cover disc and give them marks out of 100. Yes, pointless, but it keeps me out of trouble. Now OpenMediaVault off the LXF202 DVD installed fine but only boots to a CLI and I cannot get the GUI to fire up. As I keep records of all these tests (sad to say going back many, many years and several ‘spare’ computers) I note that the very same thing happened with version 1.09 of the same OS last…

Kernel updates Occasionally your distro’s package manager will want to install a newer version of the Linux kernel, the very heart of the operating system. The kernel package is unlike any other in that you can have multiple versions installed. Each package puts its own kernel and initramfs file in /boot with a corresponding set of modules in /lib/modules. It also adds a separate entry to the boot menu, so installing a new kernel leaves your old kernel available for use. This is important if you use third party drivers – those that are not included with the kernel. These often include proprietary graphics card and wireless network adaptor drivers. If you find that your wireless doesn’t work after a kernel upgrade, or you boot to a command prompt instead…

We receive several questions each month that we are unable to answer, because they give insufficient detail about the problem. In order to give the best answers to your questions, we need to know as much as possible. If you get an error message, please tell us the exact message and precisely what you did to invoke it. If you have a hardware problem, let us know about the hardware. If Linux is already running, you can use the Hardinfo program (http://hardinfo.berlios.de) that gives a full report on your hardware and system as an HTML file you can send us. Alternatively, the output from lshw is just as useful (http://ezix.org/project/wiki/HardwareLiSter). One or both of these should be in your distro’s repositories. If you are unwilling, or unable, to install these,…

An entertained home is a happy home, with the digital dream a real one, most homes have turned into a digital entertainment heaven. My home’s daily routine often revolves around keeping the tiny humans entertained streaming music, video and photos from a home Linux server (plus online services) around the home to a variety of devices. From the traditional TV with a Raspberry Pi media centre to Android tablets and Chromebooks, or through the Pi-powered projector for cinema-style fun. As software improves we like to take advantage of new features. For a while we’ve been putting up with the closed-source Plex, but finally Emby has appeared and we’re basing our new home media heaven on this fully open source solution. So from a base Ubuntu server, you’ll be able to…

OPENINDIANA 2015.10 By the time you read this OpenIndiana 2015.10, the newest update to the OpenSolaris fork, will have dropped, and it’s the first update for half a year. The new version includes changes to IPS and includes Oracle updates and numerous fixes. Python 2.7 is now also included with this release, along with an improved text installer and support for non-Grub bootloaders. If you’d prefer doing things with a graphical user interface then that’s also included, though the text installer is the one the creators would rather you use. To find out more and download the new distro head over to the official website. http://bit.ly/OpenIndiana2015_10. KAOS 2015.10 KaOS, the distribution that comes with the latest version of the KDE desktop environment and Calligra office suite – and is built…

PyConUK 2015 Lots of Python and a chance to try the Micro:bit. September 18, the first PyCon UK since the untimely passing of its organiser, John Pinner, carries on the proud tradition of promoting Python across the diverse community. The Education track has evolved and grown since its inception. For 2015 we saw the return of the Raspberry Pi Foundation, with a series of workshops covering topics, such as Pygame Zero and its recent high altitude ballooning Picademy. Python in education is a hot topic and it’s clear that this element of PyConUK is becoming a major draw for teachers. As well as workshops there was much needed time for teachers to discuss classroom ideas and listen to talks from their peers. Also present was the much anticipated Micro:bit from…

When you modify a file on one device, you expect your modification to be sent to the others, but what happens if you change the same file on more than one device between syncing? How do these programs cope, seeing as none of them include mind reading code? Rsyncand Unisononly sync between two devices. Rsyncis a strictly one-way affair, it updates the destination to match the source. Unison, which uses Rsync protocols, compares files on both sides and copies any that have been modified since the last sync. It keeps a log of what it has done in order to know what has changed. When run interactively, it lists conflicts and files that have changed on both sides, so you can pick which one to use. In batch mode it…

You need a media server, if you’re fanatical about your media – movies, TV, music, photos or whatever else takes your fancy. This is a central file server that puts you in total control of all your media, making it easy to watch and listen from any device that has access to the internet – you’re no longer tied to your living room or even your house. And better still, there’s no faffing about swapping DVDs and CDs, or having to sit through unwanted trailers. All you need for your media server is a suitably powered Linux machine. While you can add a media server to your main PC, a more convenient option is to allocate a dedicated PC exclusively to the task. Your biggest headache is choosing which media…

Before you begin, make sure you’ve allocated your server a static IP address. This gives you the same IP address each time you access your server via a web browser or SSH. To do this in Ubuntu, open System Settings and select Network. If you’re connected via Ethernet cable, select Wired, click Options and set a static address via the IPv4 Settings tab. Next, visit http://emby.media/downloads/linux-server for distro-specific installation instructions. During installation you’ll be asked to confirm the creation of a user called emby – if necessary, grant this user read/write access to your media folders. Once this is done, Emby will start running. Once Emby’s in place, it’s time to review how your media files are organised. You can store your media anywhere you like – so long as…

You don’t need to be connected to your local network to access your Emby hosted media – you can configure Emby to allow you to stream over the internet too, so you can enjoy your media just about anywhere you can get an internet connection. It pays to have a fast connection at home, ideally fibre-optic with a minimum 5Mbps upload speed – and don’t forget that streaming will quickly burn through any capped broadband allowance. If your router has UPnP switched on then Emby should work over the internet with no additional configuration; otherwise, you’ll need to manually configure port forwarding and make sure you’ve assigned a static IP address to your server PC. The settings you need to look at – and tweak – can be found under…

1 Install Emby add-on In a browser, go to https://emby.media/downloads/emby-for-kodi and click the ‘repository’ link to save the ZIP file to your drive. Now open Kodi, navigate to System > Settings > Add-ons > ‘Install from zip file’ to locate the Emby repos. Select it and choose ‘Install from repository’ > Kodi Emby AddOns > Video add-ons > Emby to install the add-on. 2 Configure add-on Click Install. When it’s done, Emby will try to detect your server – if you wish, tap ‘Yes’ and select your user. Choose whether or not to enable music, and tap ‘Yes’ to enable direct streaming for access away from home. Enter your password. Once done, click the add-on and choose ‘Configure’ to fine-tune settings – Sync Options is a good place to start.…

Blender has been used to create animations for national television channels and commercials for Coca-Cola, Pizza Hut and BMW. It creates slick marketing images for brands ranging from Puma to Philippe Starck. It has even been used on Oscar-nominated movies. And best of all, it’s open-source software. Blender is a classic underdog story. Originally the in-house 3D toolset of a small Dutch animation firm, it has survived early financial hardships and even the collapse of its original distributor to win widespread popular acclaim. With over four million downloads each year, it is now by far the world’s most widely used 3D software But more importantly for the purposes of this article, it’s software that commands the respect of professional artists. Once dismissed as a tool for hobbyists, Blender is now…

October 13th is Ada Lovelace Day. Ada is a historical figure I find fascinating, generally being credited as not only the first computer programmer but also the first to make the conceptual leap that computing devices could be used for more than just number crunching. She led an interesting (albeit somewhat privileged) life – she was the daughter of Lord Byron, became Countess Lovelace and was an acquaintance of Charles Dickens and Michael Faraday. But it is her work with Charles Babbage for which she is most famous. In 1842/43 she translated a transcript of one of his lectures on his second proposed machine – the Analytical Engine – from French to English. She produced a series of notes in addition, which explained how the machine would work and included…

Midori is a classic underdog web browser, which is trying its best to look as smooth and stylish as Safari. We can say this since the whole Elementary project, which develops the elementary OS, mimics both OS X’s exterior and general philosophy. Midori is best-known for being included in the Ubuntu-derived elementary OS and a few other lightweight distributions (distro). Midori is also the default browser in many Xfce installations as it’s valued for its speed and minimalistic design. The browser is built on top of the Webkit rendering engine and uses modern UI elements thanks to the GTK 3 and Granite libraries, which means it will fit naturally into Gnome, Unity and Cinnamon, and enabling client-side decorations (CSD) when needed. Midori saves vertical space by drawing a page-loading progress…

After running three successful Kickstarter projects now, each with over 1,000 backers and all funded well before deadline, I thought I’d share my top tips for campaigns. To do well on Kickstarter you need to have an idea that hasn’t been done before and fulfils a need, and you have to communicate that need to potential backers. It goes without saying that it’s crucial to supply a video and make sure it’s clear. Successful crowdfunding is all about good communication. If you can show your enthusiasm for your idea, people will be infected by it. Your Kickstarter page should be well written and have plenty of photos of your prototype doing cool things, but you also need find appealing ways to add value. Your page should be designed to help…

Astro Pi is a joint project created by the Raspberry Pi Foundation and the European Space Agency (ESA). The project created a hardware sensor platform, Sense HAT, that will be sent to the International Space Station (ISS), where ESA astronaut Tim Peake will run a series of experiments coded in Python by school children. The projects were created as part of a competition for primary and secondary schools across the United Kingdom. The code will be carefully checked for bugs inline with an incredibly exhaustive hardware checklist to ensure that both the HAT and the Pi are flight -ready for the trip to the ISS. Code written by the winners will be run by Tim Peake while in orbit aboard the ISS and the results will be shared with everyone.…

The CUPS printing system ships with a number of nifty little command-line utilities. In fact, you can set up and configure all aspects of your printer from the CLI. Let’s run through some of the most useful commands that will help you manage the printer better. We’ve already seen the lp command, which queues a file for printing on the default printer. The default printer is specified in the PRINTER variable. You can specify it with the command export PRINTER=printer-name where printer-name is the name of the printer you specify in step two of the walkthrough (see p66). If you have multiple printers, use the -d option to specify the printer you wish to print to. For example, lp -d HP-printer file.txt prints the file on the HP printer, which…

Our expert Nick Peers has been hooked on Linux – in particular Ubuntu and now Minibian – for 10 years. He prefers GUI-based tools, but is just as happy getting his hands dirty in the terminal. Ubuntu Xxxx Installing, fixing and tweaking printers and scanners with CUPS et al These days, it’s almost mandatory to have a printer and scanner attached to your PC, but getting them set up in Linux can be a little tricky. Don’t worry, though, because armed with the right drivers and tools you can quickly get things up and running. There are two core tools built into most Linux distributions (distros) that help simplify the process: CUPS for printers and SANE for scanners. CUPS provides a centralised management tool for adding and configuring your printers…

If, after your best efforts, you’re still unable to get your scanner set up using SANE, then take a trip to www.hamrick.com where you’ll find a program called VueScan, which promises to support over 2,500 scanners. Click the supported scanners link to browse by manufacturer – if your model is listed, then download the tarball and extract the VueScan folder, then double-click vuescan inside to launch the program proper. It should detect your scanner automatically, then provide you with a simple step-by-step wizard to preview and scan using the program. VueScan provides a lot of useful tools to help you get the perfect scan, and it works with many scanners that are already supported in Linux too, so if you’re struggling to get to grips with XSane, consider giving it…

Our expert Alex Campbell is a tech journalist who spent much of his childhood learning to build PCs and breaking things. He still loves learning new things about Linux, and he’s still breaking things a lot. BOINC Learn how to donate your CPU’s unused power to scientific projects One of the great things about Linux is the fact that people contribute their time, passion and money to different projects. That’s what makes free and open-source software so strong. The spirit of contribution to causes bigger than yourself is at the heart of Linux and free software. Unfortunately, not everyone can donate to software projects with money and not everyone can code, while others have different projects they’d like to donate their resources to. Luckily, those with philanthropic tendencies can donate…

Our expert Dr. Chris Brown provides Linux training, authoring and consultancy. He finds his Ph.D. in particle physics to be of no help in this work at all, and as you’ll sadly discover this is his final article for Linux Format. Last month, we examined the use of the sockets API for writing connection-oriented clients and servers that use the TCP protocol. This month we’re going to look at a connectionless model, using UDP. What do we mean by ‘connectionless'? Well, from a programmer’s viewpoint, we mean there are no steps required in your code to actually set up the communication – none of the connect(), listen() and accept() calls that we saw in LXF203. A client simply builds a datagram, slaps the recipient’s address on and sends it. From…

We’ve opted to use XML to serialise (store) our data. This is well-supported in Python through the ElementTree module and means that we can store and manipulate the XML tree in memory, making for trivial loading and saving. If the program cared about human-readability, a calendar containing a single appointment would look like: You’ll notice that the calendar widget is 0-indexed for the month, but nothing else. We admit this is a little strange but it’s easy to work around. Sadly, this program doesn’t care very much about readability, so everything’s stored on a single line. The XML tree object is stored in the variable self.root . The loadFile() function attempts to load it from a file, but if this is not found an empty tree is created instead. We…

Linux Format is proud to produce the biggest and best magazine that we can. A rough word count of LXF193 showed it had 55,242 words. That’s a few thousand more than Animal Farm and Kafka’s The Metamorphosis combined, but with way more Linux, coding and free software (but hopefully less bugs). That’s more than most of our competitors, and as for the best, well… that’s a subjective claim, but we do sell way more copies than any of our competition in the UK. As we like giving things to our readers, each issue the Star Question will win a copy of one of our amazing Guru Guides or Made Simple books – discover the full range at: http://bit.ly/LXFspecials. For a chance to win, email a question to lxf.answers@futurenet.com, or post…

Invisible wallpapers Q I want to place my own custom wallpapers in the /usr/share/ backgrounds folder and have them available from the default range. Unfortunately, regardless of all my attempts, including changing permissions and ownership with sudo or su , these wallpapers are still not available from the folder. In fact at one stage I couldn’t get access to any of the default wallpapers as I was gleefully informed by the system that I was not the owner – even as root. I am a relatively new user and thought that this would be easier than it transpires. Are there any other changes I need to make to have my own pictures available from the backgrounds folder? I have noted previous posts on other forums for the selfsame issue but…

As we are building a media server based on Ubuntu, you may be wondering why we haven’t put a remix of Ubuntu, containing all the required packages, on this month’s LXFDVD. After all, we’ve had desktop remixes for each Ubuntu release. The reason is that we are no longer allowed to do this. Ubuntu’s policy now forbids the distribution of modified versions of its distribution (distro) unless all references to Ubuntu are removed from it. We can’t even include a standard distro with package updates applied unless we delete anything referring to Ubuntu, which would involve recompiling many of the packages, including the kernel. This is impractical to the point of impossibility, especially when a new version is released close to our deadlines. I understand Ubuntu’s desire to protect its…

For many companies using open source software is a no brainer: you’re getting programs and suites made by some of the brightest minds in software development, free from the constraints and compromises that come with using closed source proprietary software. It can also end up saving the organisation a heck of a lot of money as well. By the start of September 2015 there were 115,013,302 lines of code in the Linux Foundation’s Collaborative Projects, which includes such initiatives as Let’s Encrypt, the free open certificate authority, the Open Container Project, Node.js and Tizen. The Linux Foundation has calculated that the total economic value of all this work is around five billion dollars. In fact, if you wanted to replicate that amount of work (and by the time you read…

You can now use Amazon Prime Instant Video to stream movies and TV shows in Linux. Going to the video streaming service’s website (www.amazon.co.uk/Prime-Instant-Video) allows you to stream videos either as part of a subscription or on a video-by-video basis. There’s some decent films on there, and Amazon has followed Netflix’s lead in producing its own TV shows, such as the critically acclaimed series Transparentand Hand of God. The Android application has also been updated to let you download videos onto your device for 30 days, which is handy for playback without using up your mobile data allowance. Google isn’t always in our good books but it’s earned some brownie points with its transport networking crew finding and fixing a Linux kernel TCP bug that has been causing trouble for…

Size matters Thank you very much for the offer to download old issues of LXF, but is something wrong with issue 175? The PDF is 172MB! Maybe you can fix this? Rene Rudolph, via email Neil says: The size of the PDF download has varied over time as bandwidth availability has changed, alongside technology too, so LXF175 is supposed to be 172MB. On feedback we reduced the size to a much lower level, but then people complained that the image quality was too poor, so the size was increased slightly again. I think we’ve found a good compromise with most issues now around 50MB. Results I’ve been reading your magazine since LXF165. Back then I didn’t know anything about open source, GNU/Linux, Raspberry Pi etc... Today I have a Pi…

Bristol and Bath LUG Meet on the fourth Saturday of each month at the Knights Templar (near Temple Meads Station) at 12:30pm until 4pm. www.bristol.lug.org.uk Blackpool Makerspace Meet every Saturday, 10am to 2pm. At PC Recycler, 29 Ripon Road, FY1 4DY. http://blackpool.lug.org.uk Edinburgh LUG Meet on the first Thursday of the month at the Southsider pub, West Richmond St. www.edlug.org.uk Hull LUG Meet at 8pm in Hartleys Bar, Newland Ave, first Tuesday every month. http://hulllug.org Lincoln LUG Meet on the third Wednesday of the month at 7pm, Lincoln Bowl, Washingborough Road, Lincoln, LN4 1EF. www.lincoln.lug.org.uk Liverpool LUG Meet first Wednesday of the month from 7pm at DoES Liverpool, Hanover St. http://liv.lug.org.uk/wiki Manchester Hackspace Open night every Wednesday at 42 Edge St, in the Northern Quarter. http://hacman.org.uk Surrey & Hampshire Hackspace…

Linus isn’t yet to achieve his goal of world domination, so we still need to be able to share with other operating systems. First off, while Rsync is available for Linux and Mac OS, there are ports to Windows and Android with varying levels of compatibility, but no pure Rsync (unless you count running it with Cygwin). Unison is available for all three desktop OSes and is an excellent choice for synchronising files across an internal network. Syncthing is available for the three desktop systems and Android (there are two Android clients in the Play Store with very similar feature sets) with a beta iOS client available recently. The OwnCloud server is a PHPweb application, although running it on windows isn’t supported, and there are clients for Linux, Mac OS,…

1 Tweak user settings The Users section of the Emby dashboard is where you manage user profiles – including your own. If you plan to share your server with other users (see p37 for more details), start by password-protecting your own user account from here: to do so, click your user profile badge and click ‘Edit this user’s profile…’ followed by Profile (you can also upload a photo of yourself if you wish). 2 Add more libraries Switch to Libraries in the dashboard and click ‘Add media folder’ to add other media to your collection. The process is identical to the one you encountered during the setup wizard: choose type and name, select a folder (or folders), then save your library and create more as needed. Emby will start scanning…

1 Set up TV server Unless you have an HDHomeRun TV tuner, you’ll need to first install a supported third-party TV package. At time of writing TVheadend.org is the only major Linux server that’s supported, so follow the main text to install and configure it alongside Emby. To test that it’s working, install Kodi and enable the TVheadend PVRplugin. 2 Add plugin Open a browser and go to localhost:8096 to access Emby’s interface. In the slide-out menu click ‘Manage Server’. Select Live TV in the left-hand pane, switch to the External Services tab, click the plugin you wish to add ( Tvheadend here), then Install. Restart the server when prompted – you may have to return manually to the External Services tab. 3 Configure plugin The plugin should appear under…

1 Access Developer mode On your NowTV remote, press the Home key three times, then up twice, then right, left, right, left and finally right again. You’ll see a screen like the above. Select ‘Enable installer and restart’, read the T&Cs, click ‘I agree’, then select ‘Enable installer and restart’ again. After rebooting, choose a password to prevent unauthorised access to your box. 2 Download and install Open a browser window and enter your NowTV box’s IP address. Enter ‘rokudev’ as the username and your password to log on. Now open a separate tab, browse to http://bit.ly/emby-nowtv, click the Emby.Roku.zip link > ‘Raw’ and save it to your Downloads folder. Switch back to the original tab, click ‘Browse’, select the ZIP file and click Install. 3 Enjoy your media When…

Even the Blender Institute doesn’t just use Blender in its animations. Here are the other open-source tools used to create its ‘open movies. We’ll be looking at some of them in more detail in future articles in this series. Krita ( krita.org ) The Institute’s main tool for concept art and storyboarding, Krita had its own resurgence. Its successful recent Kickstarter funding campaign aims to make it “faster than Photoshop”. Gimp ( gimp.org ) Although it hasn’t seen a major update for three years, Gimp is still a reliable workhorse for general image-editing tasks, such as creating the 2D texture maps used in animation or adjusting rendered stills. LibreOffice ( libreoffice.org ) The ubiquitous office suite gets used on the Institute’s movies for a…

For Colin Levy, open-source software led to a job at one of the biggest animation studios in the world. Having started experimenting with Blender while he was still in high school, by 2006 he was helping out at CG industry conference SIGGRAPH, where he met the Blender Foundation’s Ton Roosendaal. “I didn’t interact much with Ton at the time” says Levy. “But I guess he kept me on his radar, because three years later, I got an email from him, asking if I’d be interested in working on his next project ” That project was Sintel, the third of the Foundation’s ‘open movies’ – short films made entirely using open-source software, then released under a Creative Commons licence. Partly a showcase for the software and partly a way to develop…

Hopefully by now some of the following won’t be too much of a shock, but its worth spending a couple of minutes clarifying how applications hang together on a cloud based infrastructure suchas Kubernetes. I shouldsay, especiallylike Kubernetes, given that containers are what we’re orchestrating here. These entities don’t come with the heavyweight baggage of a virtual machine, but neither are they as resilient. Applications that run on containers need to take account of and plan for elements of the infrastructure appearing and disappearing from under them. For a static website this doesn’t really matter, but for any application that needs to maintain some idea of state this is crucial. This state cannot be maintained within the container itself in a non-volatile way, as containers themselves are volatile. Data that…

Sometimes you’ll come across applications that are ugly things, largely abandoned by their owners, yet still manage to be an important missing element for certain specific usecases. Paper publishing is one such area where Linux users painstakingly collect useful, and often forgotten, applications and utilities to deal with a specific problem. One example is handling the industry-standard PDF format and many users rely on Briss a small Java-based application, which uses the open source Itext and Jpedal libraries and does the simple but crucial job of cropping pages in PDF files. The application’s availability is solved very elegantly: Briss is distributed as a single archived directory with cross-platform JAR files (for Linux and OS X) and an extra EXE file for some lazy folks with Windows. Running the application in…

Who wants a 30-inch monster display when your PC is tiny? A host of topnotch new displays have been released for the Raspberry Pi. The first is the official Raspberry Pi 7-inch Touchscreen Display (http://bit.ly/LXF204piscreen), it’s a low-resolution 800x480, ten-point touchscreen that can be powered off by the Pi. At £48 it’s affordable and the Pi mounts to the back for cool projects. Kano has also released its own screen kit (www.kano.me/screen) this self-build 10.1-inch touchscreen offers a 1,280x720 resolution, but goes for the much higher price of £110. Finally, Pimoroni has gotten in on the act, supplying the display it uses as part of its Picade kit as a standalone unit. This is a cool 8-inch, 4:3 800x600 TFT display without touch, but at £45 it’s very affordable, find…

Running code in IDLE is easy but there comes a time when you really want to make your code run as an executable. The simplest way to do this is to add #!/usr/bin/env python3 as line 1 of the sensors.py project. With that change made, open a LXTerminal and navigate to the directory where sensors.py is located. To make the file executable we must change its permissions and we do this with: $ chmod +x sensors.py . So now we have the file ready to be executed and we do that in the same terminal by typing $ sudo ./sensors.py .…

1 Obtain & extract installer Browse to your manufacturer’s website and locate the required driver for your Linux distro, which may be packaged as a unified driver. Save the gar.tz file to your Downloads folder, then right-click it and choose ‘Extract Here’. Once that’s done, open the extracted folder and locate a file called install.sh. Right-click it and choose ‘Properties’ to make a note of its location. 2 Start installation Now you’ll need to open up a terminal window and type in cd <path> . You’ll need to replace <path> with the path listed under Location for the install.sh file that’s found in its Properties window. Now you’ll need to type the following command and press Enter, followed by your root password when prompted: sudo sh install.sh . After a…

While the Berkeley Space Sciences Laboratory’s SETI@home is the most famous BOINC project, there are other many great projects as well: CERN’s ATLAS@home This project calculates the data from the ATLAS experiment at the Large Hadron Collider in Geneva. University of Washington’s Rosetta@ home This project computes protein geometry to fight such crippling diseases as HIV, cancer and malaria. The University of Oxford runs the www.climateprediction.net project that computes global climate models. By adjusting BOINC’s settings, you won’t have to choose between one project or another, either. BOINC can switch between projects at regular intervals, ensuring that each project gets its own labour and love. Any researcher who needs a lot of computing power to solve a problem can create a BOINC server and host a project for relatively little…

In addition to creating TCP or UDP sockets, you can also create so-called ‘raw’ sockets, which means that the system doesn’t add a TCP or UDP header for you, though it does still add the IP header. The program has to run as root to do this. Why might you want to use a raw socket? Well, a classic example is a program such as ping, which sends and receives ICMP messages. In this case you would create the socket something like this s = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP) and your code would need to construct not only the ICMP message but also the ICMP header. When you send the packet by calling sendto(), the system adds an IP header for you. However, when you receive a packet on a raw…

We often give a solution as commands to type in a terminal. While it is usually possible to do the same with a distro’s graphical tools, the differences between these mean that such solutions are very specific. The terminal commands are more flexible and, most importantly, can be used with all distributions. System configuration commands often have to be run as the superuser, often called root. There are two main ways of doing this, depending on your distro. Many, especially Ubuntu and its derivatives, prefix the command with sudo , which asks for the user password and sets up root privileges for the duration of the command only. Other distros use su , which requires the root password and gives full root access until you type logout. If your distro…

strace What is strace? A utility that records all system calls made by the program it is told to run. What is the point of that? When the program is working correctly, not a lot. When the program misbehaves, strace shows you what it is trying to do, which files it tries to open, which library calls it tries to make. Does that help me? It can – being able to see what a program is trying to do can often help pinpoint the underlying cause of the problem. How do I run it? It prints what looks like gobbledegook to me. What do I do with it? You can look to see which system calls are failing, which should give you a clue as to where to look next.…