Linux FormatSummer 2015的目錄

Jonni Bidwell Windows 10 can’t play DVDs without third-party software. Not content with stealing recent features from Linux, they’re going after the old ones too. But what have I borrowed? In my student days I may have ‘borrowed’ some bus signage, complete with a chunk of concrete. It ended up on top of a mound somewhere in St Andrews. Les Pounder Being a Linux user for over 15 years I am intrigued to learn more about the details of Windows 10 as it’s clearly a visual history reference guide of my life using Linux every day from 1999 to the present. To make it more accurate I wonder if I will be able to change all the window decoration to brown or aubergine? Shashank Sharma Don’t speak to me about…

Linux 4.2-rc1 is now available, and considering the huge amount of new code that has been included with the kernel – it’s a bit of a whopper. According to Linux Torvalds, “if you count the size in pure number of lines changed, this really seems to be the biggest release candidate we’ve ever had, with over a million lines added ” This means 4.2-rc1 now beats the previous record holder, 3.11-rc1, which was a particularly big beast thanks to the fact that it included the Lustre filesystem, although 3.15-rc1 still retains the title for the most commits. The main reason for 4.2-rc1 being so big is that the new AMD GPU register description header, which takes up 41% of the entire patch, according to Torvalds, with 8% being taken up…

“For 115 columns Michael Meeks has been keeping us up to date with LibreOffice and the wider FOSS developments. For issue 200 we asked him to list his highlights, but ads actually sold a page and it got bumped. So here it is! LXF72, Nov 2005 I’m excited to see one of the best Linux distributions (OpenSUSE) opening up. To see the fruit of Novell’s substantial development and release engineering effort in the hands of the greatest possible number of people. The latest Kernel, Yast, Gnome, Mono, Beagle, OpenOffice, KDE etc in your hands. LXF74, Xmas 2005 The enthusiasm for the OpenDocument format as an end in itself – it seemed politicians and business people alike could grasp the open/standard formats argument… Unfortunately, this all tended to obscure the far…

Dear LXF, I am in my late 70s and have a smartphone for emails etc. I was given an Asus S200E with Windows 8, updated to 8.1 by my son some time ago. I put Kaspersky on it for virus etc and Windows Office is now gone. Problems developed and it was invaded by many unwanted ads. I had it cleaned out by Currys, but now it’s worse than ever. I suspect some incompatibility to be the cause. I purchased the magazine (LXF198) and would like to know if I can use/try Ubuntu 15.04 from the attached DVD? Hopefully avoiding the Windows problems of being the favourite virus magnet? I’ve never used Unix in my studies, Eur.Ing. C.Eng. in Materials and combustion\energy management. Can you help me decide what to…

Oggcamp It’s back! Yes the celebration of all things open source and Linux will once again open its doors to the hundreds of visitors eager to share projects and ideas at the three-track unconference. Oggcamp is two days of talks, workshops and socialising, where many projects are formed and, more importantly, friendships are made. Oggcamp 2015 will be on October 31 to November 1, Liverpool. More information will be announced via the website. http://oggcamp.org Hackference 2015 Hacking is an essential skill these days and more people are learning that it’s not an evil activity conducted for malicious intent. Hackference is a three-day event with a one-day conference with talks and workshops and a further two-day hackathon that brings the hacker community together to work on projects. The event takes place…

If you don’t want to use a pre-packaged server, why not try installing the software you need on a general purpose distribution. Even your favourite desktop distro will be a good starting point, and you can remove the desktop packages once the operating system is ready to run headless and you will be working with something familiar. Alternatively, you could use Gentoo or Arch Linux to install a server distro from scratch, including exactly what you need and no more. If you want browser based administration, Webmin is also a good general purpose option, but It’s not quite as slick as some of the interfaces that we’ve shown you here, but it works with everything. The decision rests, at least in part, on what you want a server for and…

Open Container project Docker comes together with major players to agree an open standard for containers. After a round of bickering last year between rivals for the growing container marketplace, peace has broken out amongst all the large players (noticeably including Docker and CoreOS) and an agreement to put a standard in place has been reached. The Linux Foundation will oversee the new effort called the Open Container Project (www.opencontainers.org). Signatories include Amazon, Cisco, Google, HP, IBM, Intel, Microsoft, Red Hat and VMware. Announced at DockerCon in June, the specification has been open sourced (available at https://github.com/opencontainers) and Docker has donated its format and runtime to the new organisation (known as the ‘OCP’). The OCP website has a comprehensive FAQ that outlines the reasoning behind its formation. Almost all major…

Not wanting to miss out on the current craze for all things container shaped, Amazon launched ECS (http://aws.amazon.com/ecs) last year, where the CS stands for Container Service. This uses EC2 instances to underpin Docker containers which run on top. Amazon says that the ability to use all of its other services (eg load balancing, elastic block storage) adds more value than running Docker standalone on some other service. Amazon has also signed onto the Open Container standard along with most other large industry players recently(see p48) andseemwellplacedto match other offerings as the container scene develops over the next twelve months. At the moment it does seem to me that Amazon’s offering is the equivalent of running Docker on a VM, albeit with some bells and whistles. There are moves afoot…

Summertime at Pi Towers means internships. The Foundation and Trading sides of the organisation are looking for different skills in the undergraduates they pick. Trading, for instance, is generally looking for people with exceptional low-level assembly language skills, as they’ll be working on the kernel and learning about ASIC engineering. One of the new interns has written his own compiler in his spare time and we’re very excited to see what they come up with over the summer. We’ve also taken on two students whose projects have been influential: Tom Hartley of AirPi fame, will be building demos we can use to impress people at events; and Andrew Mulholland will be polishing his PiNet (more on this next month) system, which allows teachers to easily manage classroom Pi networks. We…

The Raspberry Pi can use Bluetooth and Wi-Fi to communicate, but a new add-on called Rapid Radio enables you to add radio communication to your Pi (or Arduino) projects. The radio has a half duplex 2.4GHz transceiver, a maximum speed of 2Mbit/s and has an open area range of around 70m with a slightly improved indoor range. It’s also quite a looker, as the PCB is designed in the shape of a butterfly and is vibrant red or blue. The big selling point, however, is the ease by which you can add radio communication to the Raspberry Pi. The full source code for adding it to any project is available at GitHub, and is free to use and modify with the MIT licence. Find out more and help the Kickstarter…

Our expert Les Pounder is part of the Raspberry Pi Foundation’s Education team and travels the UK hacking the Pi to do all manner of strange things. He also writes a blog http://bigl.es. Game controllers are ergonomically designed interfaces that have evolved from paddles in the late 1970s into the multi-button, accelerometer-powered gesture controllers of today. But how hard is it to make your own controller for a Scratch game? To build this project you will need any model of Raspberry Pi, Raspbian and ScratchGPIO 7 installed on your Pi, four wine gums or other jelly-based sweets, eight paper clips, eight jumper wires (female to female). All of the example code can be found at http://bit.ly/LXF201-Scratch. For our controller we will use jelly sweets as a squishy interface. We went…

Our expert Les Pounder is part of the Raspberry Pi Foundation’s Education team and travels the UK hacking Raspberry Pis to make strange inventions. He has a blog at http://bigl.es. For this project you’ll need any Pi model and Raspbian (www.raspberrypi.org/downloads). In previous tutorials we’ve focused on creating physical projects that can be interacted with, but this time we’ll delve into the world of music using Sonic Pi. This is the personal project of Dr. Sam Aaron and the goal of Sonic Pi is to introduce creativity into programming via music and reduce the friction that’s encountered by children learning to code, eg the alignment and indentation of code and syntax errors. Sonic Pi uses the Ruby programming language created in the mid 1990s by Yukihiro “Matz” Matsumoto, which was…

Our expert Sean Conway is a senior technical specialist for an ISP who staves off senescence by designing, building and coordinating installations of operational support systems. DHCP Install and configuration of DHCP service on a Red Hat variant OS This tutorial we’ll cover the TCP/IP protocol named dynamic host control protocol (DHCP) that now does the manual work for a task that was once done by the systems administrator. In a home and small office networks DHCP services are normally supplied through the devices provided by your Internet Service provider (ISP). They are also available on home routers, including wireless versions. If you’re not using one of these devices, we’ll show how to configure DHCP yourself. In order for two hosts to communicate over an IP network, specific configuration information…

Our expert Neil Bothwick has a great deal of experience with booting up, as he has a computer in every room, but not as much with rebooting since he made the switch to Linux. File sharing Quick ways to share: from an instant web server to via your phone When we speak of file sharing, thoughts probably turn to network filesystems, such as NFS and Samba, or cloud storage services like Dropbox or SpiderOak. However, sometimes you just need to get a file from one computer to another with the minimum of fuss – something that configuring Samba doesn’t qualify for. Why not use a cloud service? They can be the simplest option, assuming you already have an account, but they have their own limitations. Some have limits on the…

The Mageia Community have set up a number of ways in which you get the latest news and support, to their own admission the goal of Mageia is the community around it. A happy community that works for the benefit of each other and not for the benefit of a company. https://planet.mageia.org/en/ collects Mageia news and blog posts from the community much like Planet Ubuntu. https://blog.mageia.org/en/ is the place to go for the latest news from the Mageia team. https://wiki.mageia.org/en/Mailing_lists if you prefer to use mailing lists. https://forums.mageia.org/en/ is the home of a lively community forum. Lastly we have Mageia’s bug tracking site, https://bugs.mageia.org which is used in a similar vein to Ubuntu’s Launchpad, in fact this is where we learnt how to install IDLE for this very tutorial. As…

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. The story that I want to tell this month has two parts. First, it’s a story of user accounts and process identity, and second, it’s a story of file ownership and permissions. Together these make up the access control model in Linux. From a command-line or system administration viewpoint this is a well-travelled road; the security model in Linux has been explained many times in the pages of this magazine. Remember, though, that in this series we’re looking through the eyes of a systems programmer. That is, we’ll be looking at the system calls and library routines that allow us to do…

You can avoid those horrid octal numbers for representing file permissions by using an equally horrid collection of symbolic constants defined in <stat.h> with names like S_ IRUSR, S_IWUSR and S_IXUSR which refer to owner read, write and execute permission respectively. For a full list see $ man 2 chmod . Each of these constants represents a single bit, so they’re intended to be or-ed together. For example the octal permission set 0644 could be written as S_IRUSR | S_ IWUSR | S_IRGRP | S_IROTH. We do, however, find this messier and harder to interpret than the octal numbers.…

The following steps download and install some necessary tools, create a scaffolded site, set up a sandbox and install all libraries; this is a relatively slow process so please be patient: After executing the yesod init --bare command, you will be asked some questions. The most important question being: is the choice of database that will be used in the project? The cabal sandbox init command configures a sandbox. The last command starts the development server. You can now access your Yesod development server by heading here: http://127.0.0.1:3000 or here: http:// localhost:3000 (the output from the development server is pictured at the bottom of this page). Note: For every project, Yesod creates a new directory. You should run the last three commands from the project directory. If you’re developing multiple projects…

Tree Graphical file managers enable you to view the contents of a directory or one of its sub-directories, as do the ls and dir commands in the shell. Most graphical managers also allow you to view directories in a tree format where you can see both sub-directories and their contents in a single view. There is an often overlooked shell command that does much the same and it goes by the unsurprising name of tree . Run with no arguments, tree prints a listing of the files and directories in the current directory and those below it. As with ls , you can pass the name of a directory to list and there are several options that alter the output. Some of the most useful are: -a – shows hidden…

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://bit.ly/Hardinfo) 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,…

If you can’t beat them, join them. That appears to be the game Microsoft is now playing. After years of active anti-open source posturing, Microsoft has totally changed tack and appears to be trying to bear hug FOSS to a happy death. When it’s not openly giving away Windows 10, it’s absorbing as many Linux features and building in Linux support into as many products as it can. Part of the Linux vs Windows feature this month looks at all the features Windows 10 has actively taken from the GNU/Linux system and how it’s possibly now more of a threat than ever before. But we’re far from worried, if anything we’re celebrating this new-found opportunity to make it easier for people to experience and use free, open source software. Linux…

Unity, the game engine that powers some of the most popular games in the world, will be getting editing tools that run natively in Linux. Games using the Unity engine can be played in Linux (as long as support is offered), however if you wanted to develop your game in the Unity Editor, you’d either need to use Windows or Mac OS X. If you were really desperate to be Linux only you could run a Unity editor using Wine emulation [see tutorials p88, LXF199]. According to Na’Tosha Bard, a Unity developer, who wrote on the company’s blog: “The story behind the Linux port of the Unity Editor is… basically a “Labour of Love”; some of us at Unity have been working off and on to port (and maintain the…

LINUX MINT 17.2 A new long term support release of Linux Mint is now available to download. It’s based on Ubuntu 14.04 and is supported until 2019. As usual it ships in both Cinnamon and Mate editions, with the Cinnamon version benefiting from a number of performance improvements. The Mate edition meanwhile gets the ability to enable and disable Caja file browser extensions at run time, and comes with a new audio library to boot. Better system settings and some nice new visual effects are also included, and you can find out more, and download the new version, from www.linuxmint.com. OPENMEDIAVAULT 2.1 A new version of this Debian-based distro for NAS devices has been made available. OpenMediaVault is primarily designed to be used in home environments or small home offices,…

Liverpool Make Fest The city shows off its passion for makery. Liverpool is the spiritual home of Oggcamp which has drawn geeks from around the world, but in June there was an even bigger event to draw in the crowds, Liverpool Make Fest. Organised by Mark Feltham and Caroline Keep, the event took place at Liverpool’s Central Library on June 27 and was hosted over four floors. The library is an immense and modern building at it was packed with the cream of hackers, makers and artists demonstrating their projects. As well as projects on display, there groups, such as Code Club, on hand to help parents learn more about coding with their children. Hackspaces such as DoES and Hac Man were also available to demonstrate the training and access…

However much we love Linux, and we do quite a lot in fact, there are a vast amount of people that do not use it, so we usually need a server that will work with other operating systems. For web and mail that’s not an issue, there are standard protocols and the server generally doesn’t care about the operating system that is being used to talk to it. However, there are some protocols designed for Windows, how well are these supported? Of most importance is the groupware facilities of Microsoft Exchange, which is considered by many to be an essential requirement for a mail server on a network that includes Windows systems. ClearOS has Zarafa as an additional (paid) option. Zarafa provides MS Exchange-like groupware services. That is, it does…

One refreshing aspect of no longer being an indentured employee of a large corporation has been the freedom to use different tools for my work. The day you realise you don’t have to use Lotus Notes ever again is a small but significant victory (in my book at least). No more bloated corporate laptop builds (no matter how well-meaning each additional bit of software is it tends to add to boot up times). No more having to seek permission to get an SSH client installed! These days I just rock up with my own kit, fire up a dedicated set of virtual machines for a particular client and get on with it. Old habits die hard though – one client insisted on giving me not one, but two laptops in…

Most of us shoot photographs and store them on a hard drive of some kind, whether that’s just our smartphone snaps or more sophisticated RAW files from a DSLR camera. Since it doesn’t take long for the amount of photos to get out of hand, most of us need a way to store, sort and organise them. In the world of Linux photo managers, Digikam is the most advanced and solid application for this job. It’s been quite a while since we reviewed Digikam last, when version 4 landed [HotPicks, p58, LXF187]. However, this splendid and heavyweight open source application shows very robust development speed, delivering good news every few months. The 4.x series is also constantly updated with maintenance releases, bringing scrupulous bug fixes as well as better multi-monitor…

The news that the Pi Foundation was going to send Astro Pi to the International Space Station (ISS) with Tim Peake was amazing, but it was even more amazing to hear that the Astro Pi was going to run experiments and code written by UK school children. After accepting all the entries, a panel of experts – including the UK Space Agency and ESERO UK – met at Pi Towers and ran through all the code on a real Astro Pi. The winning experiments included such imaginative tests as using the Pi camera to detect cosmic radiation which was designed by Magdalen College School, to a project from Thirsk School that uses offline data to geolocate the ISS, predict the country it’s currently over and display the countries’ flag. Of…

ScratchGPIO is an extensive platform for experimentation. It provides an easy to use interface for younger coders to take their first steps with electronics. It’s also a great platform for robotics thanks to the many motor control boards that are supported by it. Boards such as the Pibrella, RyanTeck Motor Control Board are controllable using ScratchGPIO. You can also control more complex platforms, such as 4Tronix Pi2Go and Agobo robot chassis. Add-on boards can be easily incorporated into your Scratch projects thanks to Simon Walters’ work. Walters is sent boards by companies, such as Pimoroni, to add them to the ScratchGPIO library. To connect to an add-on board you’ll need to install the required Python libraries and open ScratchGPIO and create a variable called Addon, using the set AddOn to…

Dr. Sam Aaron is a bright and bubbly individual who knows his craft well and loves to show others, so it’s no surprise that he’s a big advocate for Live Coding, the practice of coding in front of a live audience. Sam is part of the band Meta-ex (http://meta-ex.com), along with Jonathan Graham. Together they merge coding with musical instruments to create unique performances, where the audience can see the code transform to match the tone and pace of the music. At the recent OpenTech event in London, we saw open data, in the form of natural disaster data, being used to shape the notes used in a rather eclectic piece of music. The piece co-produced by Leah Borromeo and Jamie Perera used data sonification. However, this wasn’t a real-time…

This file is constructed using parameters or parameters with options. Parameters using option keywords are actually DHCP options, while parameters that don’t include the option text control the behaviour of the DHCP server (eg default-lease-time) or are targeted to a specific client (eg fixed-address). Depending on where parameters are located in the configuration file they either become DHCP-wide or for specific subnets. If the domain-name-servers parameter in the configuration file were moved above the subnet text, then DNS would apply to all networks listed in the file. It’s best practice to use the DHCP configuration test tool after building a configuration file. It will help identify the entries that will cause problems and prevent that problematic service from starting. When the service fails to start, be sure and check the…

The methods we have described here are fine if you are working on a trusted local network, but what if you want to share files with external devices? You can forward ports on your router to your computer to allow connections to come through, and pshs can do this automatically with UPnP, but then anyone out there can see your files. The risk is low as you are only serving specific files, and even lower with woof as it will terminate and close the port once the file has been downloaded, but there may be hidden security exploits, as with any software. Leaving the port forwarded while the program isn’t running is fine, if there is nothing listening, there is nothing to be hacked. The safest option is to use…

LaTeX is free, available on almost all operating systems and doesn’t require the latest CPU and the fastest computer. Also, if the default LaTeX styles are sufficient for you, then you can just start writing! Additionally, the LaTeX community is active and willing to help you with any problem you might have. If you type fast, then writing in LaTeX will be fast too: no more point and click, drag-and-drop or endless menu options. LaTeX is cross platform: you can easily exchange LaTeX code between different machines and operating systems, and it lets you concentrate on content as it does all the formatting for you and makes the typing of formulas and other technical content extremely easy. It’s also easy to make small changes to existing formulas or equations because…

1 Using sudo with Mageia Typically your user isn’t added to the sudo users group, so we need to check that the sudo RPM is installed before we proceed. Open a terminal and type the following: For a default install, sudo is installed as standard but this check will confirm. 2 Users and wheel group Mageia doesn’t have a user group that’s explicitly called ‘sudo’ rather it has the ‘wheel’ group and this group is where we wish to add our user to ensure that it gets sudo access. In a terminal type the following two lines to add sudo to all the members: 3 Testing our work Before our user is actually added to the wheel group we’ve added sudo access to we must logout of the current session…

A programmer chooses the permissions to assign to a file when he or she creates it (using open() or creat(), eg). However the umask is also consulted. It’s a bit mask defining those permissions that will not be granted as the file is created. The example shown here corresponds to the second example in my code. Technically, the permission set that is assigned is calculated by doing a bitwise OR of the permissions that were requested with the one’s complement of the umask.…

Our expert Mihalis Tsoukalos is a Unix admin, programmer, mathematician and DBA who enjoys writing articles and learning new ways to use Haskell. Haskell is a powerful functional, compiled programming language and Yesod is a Haskellfocsed web framework that’s for developing web applications. Yesod is an attempt to bring all the advantages of Haskell to web development work, but you will need to know the basics of Haskell before starting to write web applications with it and most of the knowledge you’ll need can be found in an introductory Haskell book. If you’re using Haskell for the first time, you can install the Glasgow Haskell Compiler on a Debian system by executing apt-get install ghc with root privileges. Yesod enables safe interactions with the outside world by automatically sanitising incoming…

This month we answer questions on: 1 Running desktop programs as root 2 Hard drive partitioning 3 Installing driver firmware 4 Running scripts from Cron 5 Changing Google’s language * Learning the new ways of Systemd 1 Root errors Q When I create a full disk image using Clonezilla on an external hard drive, for back up purposes, it’s saved as a root file automatically. Eventually it is necessary to delete the file. I can do this from the command line, but it’s quicker to use Nautilus as root. However, the terminal responds with an error message as below: Nautilus still works in spite of the error message. Can you explain the message? Bryan Mitchell A Nautilus uses DBus to communicate with the desktop session. When you use sudo it’s…

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…

A quick guide to booting problems Are you having trouble booting into your newly installed distro? Or maybe you installed some updates and now it won’t load properly. There are a few simple steps you can take to diagnose the cause. 1 Get rid of the splash screen The splash screen usually hides the boot messages, but you will want to be able to see them to diagnose the problem. You can usually get rid of it by pressing Esc, but if that doesn’t work, press e at the boot menu to edit the boot entry and remove any references to quiet or splash, then press F10 to continue the boot. This will let you see what’s going on. 2 Do you get a text prompt? This means the desktop…

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

Tox, an open source encrypted instant messaging service, has encountered a rather nasty funding problem, as the sole member of the Tox Foundation, Sean Qureshi, has allegedly – and without the knowledge of the Tox Development Team – used the Tox Foundation’s funds for personal expenses. This revelation has meant that the Tox Development Team has had to disassociate itself from the Tox Foundation, along with the tox.im, toxme.se, and libtoxcore. so domains, which the developers accuse Qureshi of “holding hostage”. It’s all a rather nasty business, and we’ve only heard one side of the story, but the Tox Development Team has postponed taking donations, which we’d suggest is the right course of action until the matter is settled. The first ever Women in Open Source Award has been given out…

Bad luck I have to tell somebody about my very limited experience with Linux. First about me – I am an oldie [but a goodie? – Ed] – and didn’t have any contact with computers until almost retired from work. I have two now – a reasonable laptop and a good desktop but both run Windows XP. I thought I should investigate eBooks. But to download eBooks requires ‘Adobe digital editions’ and this can’t be downloaded using an old OS like XP. I could pay lots of money and have my two computers upgraded to whatever Microsoft Windows is doing now, but then I saw your magazine (LXF195) with the ‘Get started with Linux’ feature and I thought that was the answer to my problem. The disk is great –…

Bristol and Bath LUG Meet on the 4th Saturday of each month at the Knights Templar (near Temple Meads Station) at 12.30pm until 4pm. www.bristol.lug.org.uk Edinburgh LUG First Thursday of the month at the Southsider pub, West Richmond St, Edinburgh. www.edlug.org.uk Hull LUG Meet at 8pm in Hartleys Bar, Newland Ave, 1st 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 First Wednesday of the month from 7pm onwards at DoES, Hanover Street, Liverpool. http://liv.lug.org.uk/wiki Manchester Hackspace Open night every Wednesday at 42 Edge St, Manchester. http://hacman.org.uk Preston Hackspace Meet at The New Continental pub on South Meadow Lane, Preston, PR1 8JP. Dates are flexible, check website for details. http://prestonhackspace.org.uk Surrey & Hampshire…

Although primarily known as a KDE distro because of its parentage, the project also produces a live-installable Gnome spin. Back in the 1990's, most distros shipped as an install-only DVD that was chock full of applications. As a nod to these good ol' days, Mageia still produces a 3.5GB DVD which features a wide range of applications and many different desktop environments, such as Xfce, Mate etc. The DVD also provides several lightweight window managers suchas IceWM, LightDM, JWM, Fluxbox, sugar and many more. If you already have Mageia installed on your machine, you can run the DVD off a USB stick and use it as a repos to install additional software. This feature should appeal to those with an intermittent internet connection, or a stiff fair usage policy. The…

We use the term ‘stability’ in this section in the Debian sense of the word, which means not changing too often – none of the software crashed while we were using it. What matters is that there is a solid Linux distribution behind the scenes, and one that will continue to provide timely security updates and fixes for significant bugs. You don’t want to be running rapidly changing software on a server, you just want it to work, and to keep on working. TheSSS is effectively the server version of 4MLinux, which is a completely independent distro. As such it has no big infrastructure behind it, making it unsuitable for anything that you might consider vaguely critical. However, TheSSS is generally unlikely to be suitable for a role where such…

Katie Miller is an OpenShift Developer Advocate and functional programmer, who is adept at many programming languages. She co-authored Getting Started with OpenShift and hosts a number of talks on demystifying functional programming. Katie is also co-founder of the Lambda Ladies group ( www.lambdaladies.com ), an online community for women who are interested in functional programming. After working for Red Hat as a software engineer and developer advocate, Katie has recently begun working at Facebook. Linux Format: Your background before was with journalism, and then you went into programming, which do you think has the best career prospects? Katie Miller: Oh, for whom? For people just coming out of school now? Um, journalism is interesting at the moment. The media industry is really in flux I think. It’s…

Barely a month seems to go by without Amazon adding something new to its cloud offering. In July the giant unveiled a new API Gateway pay as you go service, which allows anyone to quickly create the infrastructure around a (typically) REST-style interface. The reasoning here is that the work involved on an API itself can easily be dwarfed by the need to secure it and deploy it – as well as making it both scalable and able to perform well (in terms of reliability and speed). The API Gateway allows imports from Swagger (http://swagger.io) a popular API development tool to speed up deployment and will generate SDKs for JavaScript and Android that are ready for export by end users. There are a bunch of caching options available and access…

Adding an external hard drive to a Raspberry Pi is easy enough, but it does bring its own problems, thanks to adding extra bulk when you attach the hard drive. However, a new device called the PiDrive has been created, which means external hard drives and additional cables are no longer needed, and instead Raspberry Pi owners can make use of this slimline, yet large capacity, storage solution. The PiDrive connects directly into the 40-pin I/O connector of any Raspberry Pi B+, A+, or B+ v2, and then you can install any mSATA solid state drive onto the Raspberry Pi, offering much faster operating speeds and higher capacities then standard Raspberry Pi storage options. If this sounds like an appealing extra for your Pi head to http://kck.st/1RuksX3 to help fund…

Electronics is a hobby that is typically seen as the pursuit of older children and adults. But with ScratchGPIO we can enable younger children to experience the thrill of making their own hardware. Components such as LED and resistors are quite small but with parental supervision and a little instruction children can learn how to work with these components in a safe environment. Add-on boards, such as the Pibrella, UnicornHAT and TrafficHAT that provide a more child-friendly hardware interface with built-in LEDs and resistors and can be purchased for relatively low prices online.…

Minecraft on the Raspberry Pi has become the killer app to teach Python to classes and Sonic Pi has attained the same status for it’s use of music. But what if there were a way to merge the musicality of Sonic Pi with the fun of building new worlds in Minecraft? Well, now there is and from version 2.5 of Sonic Pi you can also integrate Minecraft into your musical compositions. At the time of writing this is still a bleeding edge feature but there’s a great deal of functionality, such as getting the position of the player or a block, changing the position of the player and block type and posting data to the chat window. The syntax is exceptionally easy to pick up and integrates seamlessly into the…

Here’s a reason for making half-life longer. An ISP had set the DHCP lease timeout to 24 hours for customer device connections. This provided a minimal time to push IP network changes to their devices on customer premises. An external vendors application that integrated with DHCP had an issue that impacted DHCP by rendering the service unavailable. Customers already on the network could stay on the network until DHCP leases expired, but no new customers could connect because DHCP was not available. By the time all hands were on deck to examine the problem, 12 hours of the first DHCP half-life renewal had expired. That left 12 hours before customers would start losing service if DHCP wasn’t restored. After correcting the problem a change to the DHCP lease time to…

Our expert Mihalis Tsoukalos is a Unix admin, programmer, mathematician and DBA, who enjoys writing articles and making them incredibly pretty. LaTeX Generate high quality output for music score, graphs and even fractals Donald Knuth created TeX, which LaTex is based on, back in the late 1970s as a computer language for use in typesetting because he wanted to write books. The basic output format of TeX is DVI; nowadays there are utilities that can help you generate a PDF or PostScript format without the need for generating a DVI file first. TeX had many low-level commands, and as consequence was difficult to use so Leslie Lamport decided to make it a little easier. Lamport programmed many higher-level TeX commands that lead to the creation of LaTeX. If you’ve never…

Our expert Les Pounder has been using Linux since 1999 – although he spent most of that year partying – and can be found tinkering with Raspberry Pi, Arduino and writing on his blog http://bigl.es. Mageia 5 Install, configure and get to know the latest Mageia distribution The world of Linux is multifaceted and constantly evolving to fulfil the needs of its community. We have seen so many different distributions (distros) over the years but a large proportion of them are based on two specific architectures: Debian which powers the Raspberry Pi and many different Ubuntu distros and RPM-based distros, which have been used on distros, such as Fedora and Mageia that we’re covering here. Mageia is a French distro that’s based on a fork of Mandriva, which was formerly…

The setuid mechanism was invented by the late, great Dennis Ritchie and patented in 1979 through Bell Labs, his employer. You can look it up if you want, the patent number is US 4135240. Bizarrely, the mechanism is described in the patent in terms of a logic diagram rather than a software algorithm. According to Doug McIlroy, Adjunct Professor of Computer Science at Dartmouth College: “AT&T distributed Unix with the understanding that a licence fee would be collected if and when the setuid patent issued. When the event finally occurred, the logistical problems of retroactively collecting small fees from hundreds of licensees did not seem worth the effort, so the patent was placed in the public domain.” By the way, if you’re thinking of writing a program that will run…

JSON stands for JavaScript Object Notation and is a handy way of storing information in an organised, logical and easy-to-access manner. Its main advantage is that it’s a lightweight format and therefore suitable for data interchanging. Nowadays, web services use JSON instead of XML. JSON data is built on two main structures: a) name and value pairs, and b) ordered list of values. The first structure is similar to a hash table or a dictionary, whereas the second structure is similar to an array or a list. JSON data can also have string, number, true, false and null values. Yesod offers functions for parsing and creating JSON documents that make developing web services easy; they take a JSON request as input and return a JSON response. The main benefit of…

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 it…

* Tackling the new Q I am an old-school kind of sysadmin and I’m planning on moving from CentOS 6 to CentOS 7, but Systemd is making it hard. I am hoping you know some shortcuts/tricks to help me learn the new way. I can’t spell. With init I don’t have to know how to spell things because I have tab complete. I use this for almost every command I type. How can I use tab completion with Systemd? How do I find all possible services? The init way is ls -l /etc/ init.d , but with Systemd I use which seems harder and I have to remember two locations instead of one. To list all active services in init I use chkconfig --list | grep :on but I don’t…

Favourites come and go – when we first started putting DVDs on the cover of Linux Format, the most popular distro was Mandrake and by a long way. Mandrake was a fork of Red Hat using the KDE desktop (Red Hat were unhappy with the Qt licence at the time so didn’t include KDE as an option). From a fork of an old established distro, it became a successful contender in its own right. Sadly, due to some spectacular mismanagement, Mandrake slowly faded away. Around that time, a company called Canonical forked a well-established distro and gave us Ubuntu. This became the new poster child of the cover discs. History appeared to repeat itself when Ubuntu switched to the Unity desktop and alienated significant numbers of loyal – and loud…

Best Chromebook 2015 This is the year of the Chromebook, we round up the best on the market and pick the ones to buy. Linux snapshots Set up your system for perfect filesystem snapshots, so you’ll never lose a file or entire system again. Build an Ubuntu phone How you can pop Ubuntu Touch onto your Nexus device and try out the Ubuntu phone now!…