Linux FormatAugust 2017的目錄

Jonni Bidwell I’d like to escape from having to mute and unmute my soundcard in order to stop it making terrible noises while it attempts to play music. Gotta love PulseAudioand its weird post-wake-from-suspend ways. And also psytrance (psychedelic trance), which my cohabiters describe as terrible noises. Neil Bothwick The attitude that Linux is just for Windows users who don’t want to pay for their software. Concentrating on the free (especially as in beer) aspect, detracts from the quality and range of software available. Please escape from Windows to Linux, but because it’s better, not cheaper. Nate Drake I’m mystified by the zealous frenzy of advocates of various flavours of Linux, particularly when they criticise Ubuntu for having the audacity to be flexible and easy to use. Do we want…

Since Richard Stallman released the first version of the GNU General Public Licence (GPL) back in 1989, the licence has been a linchpin of open source’s success, by guaranteeing that end users are free to run, study, share and modify any software that comes with the licence. In 2008, a case in the US appeals court (Jacobsen vs Katzer) reiterated that open source license conditions are enforceable as a copyright condition. Basically, the GPL is a licence that depends on copyright law for enforcement, and that it was a copyright licence - not a contract. You can read more about this ruling in an in-depth article at http://bit.ly/2rWiVkx. Now, a new ruling (Artifex vs Hancom) clarifies the legal basis of the GPL. This case came to be when Artifex Software,…

“At Collabora, the majority of our customers use the Linux kernel directly within their products. However, a lot of our customers are modifying the kernel to adapt it to their specific needs. While this highlights the flexible nature of Linux, it also creates a problem for these companies because they end up working with an outdated kernel that’s no longer receiving vital security updates. The kernel that shipped with its product has become so heavily modified compared to upstream versions that rebasing it on top of newer, mainline releases becomes too expensive and difficult to plan for. Staying close to upstream as much as possible , by regularly rebasing on top of new releases (typically LTS releases) is the best solution. However, for this work to be feasible, the amount…

Raspberry Jamboree 2017 Enthusiastic speeches from passionate makers. The Raspberry Jamboree was originally created by Alan “Teknoteacher” O’Donohoe, who started the Raspberry Jam revolution. But it had been left dormant for a few years and in that time the Raspberry Pi Foundation had founded their own annual event: The Raspberry Pi Party. But the Raspberry Jamboree returned in late May 2017 and found a new home, Manchester’s Central Library. This one-day unconference had two streams of talks, and in true unconference style the delegates were the ones talking about their projects, passions and problems. The Raspberry Jamboree was well attended with over 120 people taking part, and only a few days after the Manchester terrorist attack. There was also a single track of workshops, preselected and run by children and…

I wholeheartedly endorse Steve Russell’s ‘Less Geek’ letter in LXF220. I’ve recently returned to Linux Format after a spell with another magazine, which shall remain nameless, but which has recently disappeared into the back pages of another publication [the mag industry is tough – Ed]. Like Steve Russell I, too, am unlikely (at 81) ever to master the art of programming. What’s more, I find that software that’s often introduced as being intuitive is in practice far from intuitive. An example is Scribus DTP, which I’ve read about a number of occasions as being easy to master. I’ve found it anything but. (Do I hear cries of “Here, here!"?) The question I want to ask is have you ever done a tutorial on Scribus in Linux Format and if so…

Specs OS: SteamOS, Ubuntu CPU: 1GHz Mem: 512MB GPU: OpenGL 3.0+ HDD: 250MB Descend into an otherworldly tale in which an antiques deliveryman searches for an address that may not be real. The only way to reach it is via a similarly existentially challenged highway: Route Zero. What follows is a dream-like journey through a rural nightscape, evocatively rendered in an aliased vector style and accompanied by swelling ambient score. There are no explicit puzzles here, except for the meaning of the things you experience along the way or riddles proffered by your occasional companions. Characters fade from reality like apparitions, a radio booms out choral music in a deserted church, a burning tree marks a turning along the highway, and an old tannoy pings the depths of a disused…

Set up a VPN and it typically just works, without you having to do anything at all. But as usual with networks, any issues you have can be complicated, so it’s important your VPN has a support system to help out. Buffered VPN has plenty of web articles, including one on setting up the system for Linux, but it’s distinctly short on detail. If you have problems you can also contact its tech support people 24/7 via email, and live chat is available sometimes. Mullvad’s web knowledge base also has very brief articles, but it covers many more areas. Instead of a generic Linux install paragraph, for instance, you get separate details for different distros. There are guides on specialist topics, and email support is available. SlickVPN has a well-presented…

The default runlevel is specified in the file /etc/inittab , and the line id:5:initdefault: says that this system boots to runlevel 5 by defaults. That can be changed by editing the file or by adding the runlevel to the list of kernel options when booting. If you sometimes want a desktop and sometimes not, you could have separate bootloader menu entries to enable you to choose between them. You can change runlevels after the computer has booted with the telinit command. If you booted to a text console and now want a desktop, you would run, as root $ telinit 5 Systemd doesn’t have runlevels, and its equivalents are targets: multi-user.target is the equivalent of runlevel 3 while graphical.target matches 5. The equivalent of the above telinit command to switch…

We recently had to create a timelapse video using images, and the first obstacle we faced was converting the timestamps into an ascending numerical order of images. Luckily, and thanks to a little BASH magic, we found a one-line shell script that managed to convert the timestamp images into numbers. We did this with a copy of all the images, to ensure that we had backups. So why did we capture the images with a timestamp? Well, this project can be used in scientific experiments, so capturing the time and date of each image means that we can review when a change took place, say watching cress/sunflowers grow. Now to create the video we used avconv. This can be used with the Raspberry Pi. To install it, open the Terminal…

Chocolate Doom supports multiplayer with minimal fuss. Unlike Vanilla Doom, you can play Chocolate Doom either over the internet or via LAN (local area network). To keep things simple, however, make sure all the players who wish to take part are running Chocolate Doom and using the same WAD file before going ahead. Whether you play multiplayer over the internet or via a LAN, one of the participating players must act as the server and host the game. Rest assured that the host player will be able to play the game too. UDP port 2342 must be open on each player’s router and/or firewall. (see The Doom is in the Details, above). To host a Deathmatch game on your Pi, open Terminal or connect via SSH and run the following…

If you’ve enjoyed this taste of the Complete Ethical Hacking Udemy course, you can gain full access to the full course at udemy.com with this exclusive Linux Format reader discount*. You’ll discover a full working knowledge of performing ethical hacking, penetration testing, web testing and Wifi hacking, in a safe environment. You’ll also gain advice on channeling these skills to a freelance hacking career, and much more.. Visit http://bit.ly/ETHICALHACKING10 to enroll in the course at a discounted price of £10 (95 per cent off). Click the Buy Now button and sign up for an account on Udemy. Once you’ve signed up for an account, you’ll be asked to confirm your purchase. The discounted course price of £10 will be applied automatically with the code ETHICALHACKING10. Input your credit card information…

Unlike DVDs, Blu-ray playback is more problematic in Linux (see LXF223) thanks to the presence of two different forms of encryption. Older discs encoded using AACS encryption are more likely to work with this method, a few BD+ encrypted discs may work if you’re lucky – it’s a case of plug and pray! The following commands install the required libraries along with VLC Media Player, which you’ll need in order to watch your Blu-ray: Once installed, pop your Blu-ray into the drive and invoke VLCfrom the command line: substitute /dev/sr0 with the path to your Blu-ray drive and if the disc is supported it should automatically launch the main feature.…

When mimicking water, or anything that behaves like a fluid, a particles system is used. The point of the system is to mimic real-world physics as close as possible, and the easiest way to understand this is to play with ping-pong balls. Use a bowl and look carefully as they fall into the bowl. Better still, film the balls as they drop and then replay the action frame by frame to get a feel for how they move. A program’s particles system calculates a particle’s trajectory by taking into account the initial speed, rigidity and the speed of other nearby particles. In the case of water, it also considers how many particles merge into one, which is known as smooth collisions. The odd thing here is that to calculate the…

1 Download Duck Encoder Open Terminal on your machine and make sure Java is installed by running sudo apt-get install default-jre. Download the Duck Encode by running the command wget https://github.com/hak5darren/USB-Rubber-Ducky/blob/master/duckencoder.jar. Next, insert the Duck microSD card into the reader, then plug the reader into a vacant USB port. Check the exact name of your card in your /media folder, for example / media/nate/A87B-A154/. Then reopen Terminal and run nano helloworld.txt to create a text file. 2 Prepare your payload Paste the following: Press Ctrl+X, Ctrl+ Y, then Return to save the payload and exit. 3 Execute the payload Next, run java -jar duckencode.jar -i helloworld.txt -o <sd location>/inject.bin, replacing <sd location> with the relevant location on your system. Use your File Manager to eject the microSD card safely or…

Our expert Jonni Bidwell begins each working day with a cup of tea and a new DE. By the end of that day he’s finished configuring it to his whim, ready to start work tomorrow. By now most sane people have stopped talking about “the year of the Linux desktop”. There was a time, right around when Windows Vista was released, where there might have been hope that the Windows and Mac goliaths would be slain. But OS inertia is hard to overcome, people get locked into nasty proprietary habits and now that kant is the stuff of fairy tales. Not that it matters - the Linux desktop ecosystem has never been healthier, it’s just an area of special interest rather than a major player. As casual computing becomes more…

KDE development moves pretty swiftly, in some cases much more swiftly than distros can keep up with. For example, Plasma 5.10 was released at the end of May, and the KDE Applications bundle will be refreshed in August, but the upstream release needs to be carefully packaged and tested by each distribution, and often (say, if an update requires some fundamental bit of Qt to be updated) won’t be included until the next release. Such release frustrations are commonplace, and while they can be assuaged through the use of third-party repositories (such as the Kubuntu Backports PPA) the results may be unstable. For this reason KDE maintain its own system, based on the Ubuntu LTS release and featuring the latest KDE stack, called KDE neon. It’s not correct to call…

ClamAV is the free and open source multithreaded virus scanner developed by Cisco systems after its acquisition from Sourcefire in 2013. It might help to have this installed on the new ISO as well, just in case the reason why you were attempting data recovery in the first place was because of a virus. However unlikely it is that the system is compromised with a virus, having ClamAV pre-installed might be handy along with some other software. Another useful software to have would be AIDE. Note that it only carries out file integrity checks. It can’t check for signs of rootkits or take a look inside the logfiles for anything suspicious. For that you’d want to take a look at something like logwatch. For rootkits we recommend chkrootkit, as do…

The aim of this tutorial is pretty challenging: you’re keen to increase the security of your company or your home, and you’re looking for easy ways to have better, more secure passwords that are difficult to guess. The idea is to write a program in any programming language that will do the work for you. Although a problem might look simple at first, its solution might be complex, so don’t underestimate simple problems. It would be good to start thinking about the problem on your own and perhaps write some small programs, but of course you should also read this tutorial for advice.…

There are many types of algorithms, which are based on mathematical formulas, that enable you to calculate pi with the desired accuracy and have more control over the process. The main disadvantage of this approach is that you have to write the code. However, when you have your own implementing of an algorithm, it’s easier to optimise it and thus make it faster. The list of techniques that make it possible for you to calculate pi to arbitrary precision includes the following: Bailey–Borwein–Plouffe formula, the Bellard’s formula, the Borwein’s algorithm, the Chudnovsky algorithm, the FEE method, the Gauss–Legendre algorithm, the Leibniz formula, the Liu Hui’s algorithm for pi, the Viète’s formula, the Wallis product and the Zhao Youqin’s pi algorithm. Most of the aforementioned techniques calculate the summary of a…

Don’t use Linux because it’s free, but because it frees you and your hardware. We’re not here to bash Windows, we’re here to give you choice. When you buy a Mac you have to run MacOS. Buy a PC and you’ll be steered in the direction of Windows 10. I’m not even going to mention tablets, phones, TVs and even cars. All are examples of companies attempting to lock-in consumers to a walled software ecosystem. When you own the hardware, why is the software you can run being dictated to you? The PC is a general-purpose computing engine. It should and usually can run any software you like – though recent examples show even the PC is being walled off through its firmware. That’s where open source Linux-based OSes come…

TANGLU TLE 4.0 Tanglu 4.0 – codenamed Dasyatis – has been released. This update to the Debian-based distro has been a long time coming, as the release announcement explains (http://tanglu.org/blog/2017/06/tanglu-4-dasyatis-kuhlii-released). “Tanglu 4 comes – due to being frozen for far too long – without the latest and greatest packages, but still with some notable changes. The KDE Plasma version is at 5.8, while the GNOME desktop is available in version 3.20 with some pieces from GNOME 3.22.” Tanglu now ses usrmerged by default, and it now supports installing on UEFI systems without legacy mode. Head over to http://tanglu.org/download to find out more. ROSA R9 “LXQT” Rosa R9, a distro that features the lightweight LXQt 0.11 desktop, has been released. Designed for low-powered devices such as netbooks, Rosa R9 can easily…

Derby Mini Maker Faire On Saturday October 28, Derby will celebrate its sixth Mini Maker Faire. If you haven’t been to a Maker Faire event, then the basic premise is that it’s a space for makers to show their projects, and for the public to sample the many different aspects of the maker community. The organisers are looking for makers to submit their projects and secure a stall. So you should check out the website, grab your tickets and submit your ideas! https://makerfairederby.com Mozilla Festival The Mozilla Festival (MozFest), is a three-day conference, festival and unconference for every facet of our digital lives. Taking place on October 27-29 at Ravensbourne College, London, this festival offers workshops and talks on digital privacy, journalism in the 21st century and new emerging technologies…

We’ve tried to select VPNs that offer a little more than the usual service, but if you’re happy with the privacy basics, there are plenty of more mainstream alternatives around. IPVanish (www.ipvanish.com) claims to be the “world’s fastest VPN” with 500+ servers in 60+ servers. It’s speedy, and has Windows, Mac and mobile clients, although Linux users will have to set up the system manually. VPN Unlimited (www.vpnunlimitedapp.com) has a Linux client and low-cost weekly plans. PureVPN (www.purevpn.com) also gives you a Linux client and servers in 140+ countries, and NordVPN (www.nordvpn.com) can route its traffic over Tor for an additional level of protection. Don’t rule out free VPNs entirely. Many have strict bandwidth limits – 500MB a month is typical, sometimes it’s even less – but Windscribe gives you…

Most Linux distro’s desktop do a good job of masking the fact that Linux and Windows are different operating systems. There’s the small matter of the filesystem of course, while Linux is much tighter with security than Windows. Windows has closed the gaps in some areas – file and folder permissions, for example – but in others Linux remains way out in front. For example, you can’t perform an administrative task in Linux – such as installing a program – without supplying your user password. It’s this attention to detail that makes Linux far less vulnerable to malware and hackers. Despite appearances, Linux remains an operating system that performs best from the shell environment. Ubuntu has a good front end, but as you’ll see, don’t resist embracing the command line…

The Terminalprovides a host of tools for divulging key info about your hardware. Start with the following command for a table-like summary of your hardware (list hardware): $ sudo lshw -short You can also output a full-blown detailed report for viewing in your web browser: $ sudo lshw -html > sysinfo.html Other related tools include lscpu (list processor information), lsblk (list block storage), lspci (list internal hardware) and lsusb (USB devices). They all work slightly differently – for example, sudo lspci -v provides a handy summary, while lsusb works best if you first identify the device you wish to check out via sudo lsusb , then use the following command based on its bus and device number: $ sudo lsusb -D /dev/bus/usb/00x/00y One final tool – dmidecode – can provide…

One of the first things init does is mount your filesystems. The kernel will have mounted the root filesystem when it started, but it’s often mounted read-only. Mounting filesystems is controlled by the contents of /etc/fstab , which lists the devices to mount, their mount points and any options to use when mounting them. The root filesystem is remounted read-write, then the other local filesystems, including swap, are mounted. Any filesystems with the noauto option set aren’t mounted and network filesystems are left until the network is available. While this task was traditionally handled by init , things have changed recently. It can no longer be guaranteed that everything needed for early boot is on the root filesystem, particularly on systems that use a separate filesystem for /usr , so…

We’ve talked about what happens when you start your computer from cold, and touched on what happens when you shut down, but that isn’t the only way of turning a computer on and off. Sleep and hibernation are ways of turning a computer off without turning it off. They save the computer’s current state and restore it when it’s turned back on. This saves time on both shutdown and startup and also means you can carry on where you left off with all your applications still open. While originally intended for laptops, sleep and hibernate are becoming increasingly popular for desktops too. In sleep mode, the computer enters a low-power mode where the contents of memory are preserved but most other functions are shut down. This gives instant restarts but…

If you’re looking to wipe Windows from the drive and install Ubuntu on its own, then the process for installing it is straightforward. If there’s nothing on the disk you wish to keep then simply wipe the entire drive during the regular installation process by selecting ‘Erase disk and install Ubuntu’ at the ‘Installation type’ screen and clicking Continue. You’ll then be shown a screen telling you that you’re planning to install Ubuntu on the selected disk (/dev/sda) and that the entire disk will be used. If you have a second hard drive installed you can install Ubuntu here, too – again, that disk will be wiped and everything given to Ubuntu. But what if you’ve got a multi-partition setup with a separate data volume and you’d like to keep…

SAME, SAME BUT DIFFERENT “Each packaging system has its quirks, but they all have a lot in common, too.” Joe Damato is a low-level computologist and the creator of packagecloud.io , a site that offers free and enterprise repository hosting for packages of all formats, shapes and sizes. They range from the .debs and .rpms we’re all familiar with, to more exotic things like Maven repos. It can talk to all manner of build/orchestration/ continuous integration systems, including but not limited to Chef, Puppet, Jenkins and TravisCI, and generally takes the pain out of software distribution. We caught up with Joe at OSCON Europe 2016 in London, where he gave a fascinating talk entitled “Infrastructure as code might be literally impossible”, in which he talked about the…

Our expert Nate Drake is taking a well-earned sabbatical from treasure hunting and dodging dodgy mercenaries. He now [foolishly–Ed] works as a full-time freelance technology journalist. Despite the clichéd plot and clunky graphics, id Software’s Doomhas enjoyed huge popularity since it exploded on to PCs in 1993. It helped cement the first person shooter (FPS) genre of video games, and spawned a number of sequels, spin-off games and fan-made levels. Even those who are too young to remember when Doom was initially released will likely be familiar with the FPS genre. Because Doomis the most iconic FPS of them all, it’s important to recreate the original ’90s experience as closely as possible and for this reason we’ve selected the Chocolate Doom Engine to run on your Raspberry Pi. This project…

Our expert Nick Peers has an unhealthy obsession with digital media, not helped by his determination to drown in a sea of DVDs, Blu-rays and CDs as he attempts to amass the ultimate digital media collection. Multimedia plays a key role in computing, and you don’t need to be logged into the desktop to be able to enjoy your collection of music and video files, and photogrphs. The command line also provides access to a host of tools that enable you to rip, encode, convert and tweak your media files. Let’s start by making sure Ubuntu has full multimedia support. Even if you ticked the box to install third-party software during the install process you’re still missing several key elements. First, let’s install all of those “restricted” extras, not just…

Our expert Mats Tage Axelsson Mats Tage Axelsson has spent decades making his computers run Linux. In the last issue, he showed you what animation software to use. Now, learn to animate. By the end of this article you’ll have learnt how to animate a boy walking up to a basketball hoop, before shooting and scoring. This may not sound like much, but as you’ll soon discover, there are many details to consider because we have to create and control everything that the viewer sees on the screen. The scene is built up from a background and contains people and objects: a playing field, a ball, a basketball hoop and the boy. Each element is relatively simple to draw – the ball is just a sphere, after all – but…

You might think that grass is easy to depict: just draw some bent green lines. The reality is that it seldom looks natural and you certainly don’t want to draw multiple blades of grass yourself. Fortunately, the mathematics are fairly simple which makes it perfect for using the computer to calculate the grassy lawn for us. Adding some randomness completes the natural look. Each straw will be defined by a few angles between the ends, called control points, of an open triangle. When you design the straw you will have two lines connected in the middle, where the ends of the lines are the control points that you can manipulate. The maths element calculates the midpoint of a reference line between the two lines. The reference lines ends are always…

Our expert Jonni Bidwell is gripped by election fever. What asinine policies will be forced on us next? What basic rights do we no longer need? The operating system kernel lies at the heart of all Linux systems, from the smallest embedded or mobile device, to the largest supercomputer. Remarkably, across the broad spectrum, the kernel has the same essential tasks. It controls access to hardware; competition for resources between different applications and other tasks; handles I/O activity, and files and data storage; security; networking and so on. By selecting kernel command line parameters at boot time, the system can be made to behave in many different ways. In this tutorial we continue our showcase of the Linux Foundation’s Essentials of Linux System Administration course LFS201. In this outing we…

Unity die-hards [where?!-Ed] who are concerned about the shift to Gnome in the next Ubuntu release shouldn’t worry. For one thing, Unity 7 will remain available in the repos. Meanwhile, the nascent Unity 8 has been adopted by the community and will evolve accordingly. However, having a Gnome desktop that vaguely resembles one’s former home might provide a pain-free transition to this brave new desktop world. We’ve already mentioned the popular Dash-to-Dock extension, which provides the dock that new Gnome converts will likely miss. This can be tweaked, either from Gnome Tweak Tool or the extensions website, to make things more Unity-like. It can adopt the characteristic placement on the left hand side of the desktop. Dash-to-dock can include the Applications menu from the activities overview, and it can be…

Our expert Mark Chisholm Arch keeps Mark at the forefront of the Linux world. He’s been maintaining MorpheusArch Linux, which specialises in data recovery. Judd Vinet, the creator of Arch Linux, famously said that Arch Linux is what you make of it. With this in mind, we think Arch Linux is the ideal foundation to start assembling your own custom distro. This tutorial will be mainly focused on data recovery, because having a recovery disc will benefit both the average home user and the seasoned sysadmin, and nothing beats the feeling of knowing you built it. Along the way we’ll show you ways in which you can customise it further to suit almost any task, including pen testing. Arch Linux might not be as customisable as a Gentoo install –…

Using the dd command can actually destroy data as opposed to recovering it, but only if used incorrectly. An example of the proper usage can be found in this command # dd if=/dev/target_ partition of=/home/user/partition.image . The if=/ part of the command must be first in executing the command and never the of part. An easy way to remember this is by thinking about the alphabet. I is before O so execute the if section before the of section. Other examples of the dd command are as follows. # dd if=/dev/sda of=/dev/sdb would back up the entire contents of /dev/sda/ to drive /dev/sdb/ , but just be sure to verify the drive with the lsblk command. You could even create a Cron job with a BASH shell script to run…

Random numbers are useful in many different areas – one of them is the generation of random strings. As a result, this tutorial will first generate random numbers and use them to generate random strings. At the end of the day these random strings will be used as difficult-to-guess passwords. Strictly speaking, a sequence of numbers is considered to be statistically random when you cannot find any recognisable patterns or regularities in it. Each sequence of random numbers starts with value that is named seed – therefore the seed is the most important property of a random number generator because it initialises the entire process. The seed itself does not need to be random or difficult to guess and is usually generated from the system clock or some other system…

Because the time()utility is used in this tutorial, it would be nice to learn how to interpret its output. So, the time()utility executes the specified command as usual while collecting timing statistics about it. The statistics are printed after the command finishes its execution. The timing statistics come in three categories: real, user and sys. The real value shows the actual time it took the command to execute from start to finish. The user value is the CPU time spent executing code in user-mode, whereas the sys value is the CPU time that the program spent executing code in kernel mode. If you add the user and sys values you’ll get the total time of CPU time. However, if you’re using a machine with multiple CPUs and cores, the CPU…

There used to be a saying: “Linux is user-friendly, it’s just very selective with who its friends are.” That’s not the case nowadays because Linux has become ever easier to get into for new users. This month’s DVD contains three good examples of how a distro can be configured to be easy to grasp for new users, but also benefit more-experienced users. The thing about being a newbie, at anything, is that it’s a temporary status – after a while you’ll either gain experience and proficiency, or you’ll give up. The three distros will appeal to those coming from Windows, but they’re still Linux distros. Linux isn’t just a free operating system for those not wishing to pay for Windows. It’s a separate OS and as such, it does things…

A Sudovulnerability has been found – and quickly patched – that enabled a local attacker to gain root privileges. The issue, known as CVE-2017-1000367, made it possible for malicious users to run bash commands to overwrite files – even root-owned data. The security researchers from Qualys revealed that, “We discovered a vulnerability in Sudo’s get_process_ttyname() for Linux: this function opens “/proc/[pid]/stat” (man proc) and reads the device number of the tty from field 7 (tty_nr)”. Red Hat, Debian and other distros – especially ones with SELinux enabled, have been patched. To find out more read the security advisory at http://bit.ly/2rry8GJ. There are now 3,500 Linux games on Steam, the popular store (and DRM enabler) for PC games. These titles range from quirky indie games such as Terrari, to blockbuster games…

“Over the past decade we’ve seen virtualisation fully mature in the data centre. It’s now beginning to move into the embedded space – largely thanks to the low-power devices being produced by Intel and ARM. Virtualisation provides these environments with the same benefits it has for the data centre. First, it makes possible the merging of workloads on to a smaller set of hardware, which reduces costs, power and space usage. Second, the abstraction of the hardware makes it possible for applications to be decoupled from hardware specifics. And third, the benefit of hardware-based isolation results in better protection against software defects – and if any failures occur, they can be contained easily. The hypervisor plays a key role in the virtualisation of embedded systems, especially in use cases like…

Missing bits Way back in the 1990s I developed The Digital DJ Dance Manager, which ran on a PC with Windows XP Pro. While it was written using Visual Basic 6 I would like to clean it up and rewrite it to run on Linux. The unfortunate thing is that this program enables one to use seven simultaneous displays, which isn’t easily done with any of the Linux distros I’ve seen. While the current release of DJ isn’t pretty, it does get around the irritations which the use of Tabs pose when using an iPad! One display with tabs is not conducive to programs like this, or for businesses such as stocktaking, banking, purchasing and particularly like multi-display video gaming. When is Linux going to make it easier to add…

Comparing VPN prices is more complicated than you might think. Some services have free plans, others offer monthly payments, and sometimes you can save by signing up for even longer. If you’re looking for a simple yearly plan, SlickVPN gives you the best deal at £3.20 ($4) a month. Buffered VPN costs more than twice that at £6.60 ($8.25), IVPN is similar at £6.66 ($8.33), and Perfect Privacy is the most expensive of all at £8.84 ($11.05) per month for a one-year plan. If you just need a VPN occasionally, paying for a single month could make more sense. Mullvad wins out by charging only £4.24 ($5.30), while SlickVPN’s single month charge is £8 ($10), Buffered VPN £10.40 ($13), Perfect Privacy £11.46 ($16.86) and IVPN is a monthly £12 ($15).…

“You’ll gain the grounding you need to help you make the move from Windows to Linux.” However familiar you are in Windows, you can’t transfer everything you know and apply it equally to your new OS, and that’s particularly true when it comes to Linux, even a modern user-friendly one. Some things can translate, of course, but there are still fundamental differences in the way Linux operates and works that you need to understand. We’re going to base this guide on Ubuntu 16.04 LTS (www.ubuntu.com/download) which is the base for a host of Linux OSes, including ones on the LXFDVD, as you’ll discover part of the fun is the variety of choice in the Linux world. We’ll begin by examining the Linux filesystem (everything is a file, even your folders…

While a standard Linux desktop like Ubuntu’s Unity or Gnome provides a familiar point-and-click environment for performing day-to-day tasks, it’s still no match for the power and versatility of the Linux “shell”, the underlying command-line environment. And thanks to the Terminal, you can interact directly with the shell without leaving the desktop. The standard Linux shell utilises a language called BASH to run specific commands using a series of tools. Each command follows the same basic structure: $ utility <command> -option The utility portion of the command is the tool that you wish to run – for example, cd to change directory, or apt-get to trigger the software install tool. Some utilities can be run on their own – type ls and you’ll get a basic list of all files…

When you open the Terminal, you log on to the shell via your own user account. Certain commands require elevated access as the root user (look for a ‘permission denied’ error), and you achieve this by preceding the command with sudo , like so: $ sudo apt-get install vlc You’ll be prompted for your own user account password, and the command will now run – you should now be able to use the sudo command again during the Terminal session without being prompted for your password. By the way, if you forget to include sudo from a command, just type sudo !! and hit [Enter] to repeat the command with sudo applied to it. If you want to launch a desktop app with root privileges (such as the Nautilus file…

Linux is the kernel, that one file in /boot . Everything else, the rest of the GNU/Linux operating system, runs on top of that kernel. The kernel is the core of the OS: it sits between the hardware and the rest of the software and everything passes through it, but it’sn’t the complete OS. So where exactly is the operating system? Remember the root= parameter that the bootloader passed to the kernel? That’s where everything else starts. It starts with a program called init, found in /sbin by default. Init’s the first program the kernel runs, it always has the process ID of 1, everything else is a child of it. This is one of the factors cited in the arguments against systemd, in that it runs as init, as…

The boot process of a modern operating system is certainly complex, even if the specific details are normally hidden out of sight from you. It’s also well tested and most of the time it works just as it should. Of course, “most of the time” usually applies to other people, so what can you do when things go wrong for you? The first step is to disable any splash screen so you can see what is going on. If a particular service is failing, then you can try booting into runlevel 1, single user mode, and then disabling that service. The upshot of this approach is that you may end up with a slightly crippled machine, but you’ll be able to work with it to fix any problems. If you…

When Ubuntu is installed, it adds a boot manager called GRUB, which should detect Windows and enable you to switch between loading Ubuntu and Windows on every startup. Sometimes this doesn’t work – particularly if you’re forced to partition your drive manually – and Windows isn’t detected. Here’s what you can do to try and bring it back. First, boot from your Windows rescue media and choose the option to repair your PC. This brings Windows back, but removes GRUB. Next, boot from your Linux install media and choose Try Ubuntu when prompted. Now open a Terminal windows (press Ctrl+Alt+T) and type the following: $ sudo add-apt-repository ppa:yannubuntu/ boot-repair $ sudo apt-get update $ sudo apt-get install -y boot-repair && boot-repair Next, open Boot Repair from the Dash and choose…

“It’s just the kind of video editor that you’ll want to get to know.” Video editor Flowblade Version: 1.12.2 Web: http://bit.ly/2rM2Ui3 Even in the post-camcorder era, people still generate countless gigabytes of video content. Most of it comes from their smartphones and remains, for the most part, unedited and unloved. The Linux Format team believes that these files shouldn’t be forgotten or stored as a dead weight on a hard drive, so let’s make better use of them by producing some cool home videos. When placed alongside the most well-established non-linear video editors in Linux, such as Kdenlive and OpenShot, Flowblade is a lesser-known rival. Don’t let its obscurity put you off, though. The program is just the kind of video editor that you’ll want to get to know, and…

Recently, I wrote some code to use the DS18B20 temperature sensor with Python via a function. The code was based on the code used with the Cam Jam Edu Kits, a code base that I’d used for nearly two years. Now this code was quite large, and only printed the temperature to the Python shell. But after a chance conversation with Ben Nuttall from the Raspberry Pi Foundation I learnt of a library called W1ThermSensor that handled all of the hard work! The library, written by Timo Furrer, is awesome and it helps abstract the steps necessary to read the one-wire sensor, which appears as a file in the Linux file system. Take a look at the library and try it out: https://github.com/timofurrer/w1thermsensor. The next step for using this sensor…

Our expert Les Pounder Les is a freelance maker and hacker who works with the Raspberry Pi Foundation to deliver its picademy training. Les writes about his adventures on his blog: http:// www.bigl.es Using the Raspberry Pi camera for timelapse is a simple project, but ensuring that the subject of your photography is lit correctly can be a little tricky. In this project we shall create a timelapse controller that has analogue controllers for the brightness and contrast of the images to be captured. The files saved will also have a timestamp to ensure that they’re captured correctly and can be reviewed in chronological order. So let’s start by building the hardware. Circuit city To build the circuit for this project we need to place an MCP3008 analogue-to-digital converter onto…

Chocolate Doom mirrors the original closely, including the built-in cheat codes. These can be used at any time during play, simply by typing them on the keyboard. In most cases you’ll see a message confirming that the cheat has been activated. The cheats below assume you’re using a QWERTY keyboard. Cheats can work in multiplayer Deathmatches, depending on the settings made by the person setting up the game. Add the flag – nocheats to prevent others from having an unfair advantage. A few select cheats in no particular order are: idchoppers: this cheat will equip you with the chainsaw. Press 1 to select it. idclev##: use this cheat code to warp to the episode or map of your choice – for example idclev02 would take you to map 2. iddqd:…

Our expert Ermin Kreponic is an IT expert and Linux enthusiast with a passion for troubleshooting network-related problems. He does not sleep much. This article is all about sslstripand ARP spoofing. Attacking wireless networks is about much more than just cracking the authentication keys. There are a lot of other techniques that can be used, especially on public Wi-Fi where you can authenticate without any problems. Once you’re authenticated then you’re able to listen to all the traffic on that network. More likely than not, however, that traffic will be encrypted and probably won’t be all that much use to you. You’ll be able to see which IP addresses are visiting what websites, but you won’t be able to see anything of real value to an attacker. The problem is…

If you’re looking for a way to quickly rip CDs to your PC from the command line, then try Abcde ( sudo apt install abcde ). It’s basically a script that links other tools – CD-ripping software, encoders, CD identification and tagging tools, and so on – to provide an all-in-one solution to rip your CDs with the minimum of effort. After installation (choose No configuration if prompted during setup) you’re ready to go, with the following basic command: Other output options include vorbis (for ogg), FLAC, m4a and the default WAV. You may be prompted to install additional software (Abcde requires eyeD3 to tag MP3 files, for example). After launching, the CD will be matched to the cddb database. You’ll be asked if you want to manually edit this…

The primary reason for creating an animation is to tell a story. And to gain your audience’s attention and make sure they follow the story from beginning to end, we’d suggest taking your character on a journey, preferably with some difficulties [a Deathstar perhaps?–Ed] to overcome along the way. The best way to plan your animation and get a good overview of your story – especially if it’s a lengthy production – is to create a storyboard called an animatic for animations, it contains the major events in your story. This animatic displays the key positions and movements for all scenes. This makes it possible to start any of the scenes and any character in any position. If a team is doing the job, then each member can take on…

Our expert Nate Drake Freelance technology journalist Nate specialises in writing about cybersecurity. He’s quackers about this pen-testing device. Computers trust humans. Humans use keyboards. This means if the wrong sort of person had physical access to your computer keyboard, then they could wreak all kinds of havoc. The USB Rubber Ducky, despite its benign name, is one such device. In technical terms it’s an evil HID (human interface device), which can plug into a computer or mobile USB port and run thousands of commands in the space of a few seconds. Fans of the TV series Mr. Robot may remember that the character Angela Moss used a Ducky in this way on FBI computers with devastating effect. The origins of the USB Rubber Ducky device can be traced back…

Sign up for any Linux Foundation training course today and enjoy a 10* per cent discount off the normal price! The experts at the Linux Foundation have created courses that span the entire range of Linux, from classic Sysadmin courses to emerging technologies such as OpenStack and Open Daylight. If you’ve enjoyed this small sample and want to learn more, we’ve take this segment from the highly popular LFS201 Essentials of System Administration course, that comes with the optional Linux Foundation Certified Sysadmin qualification. The course is entirely online, is self-paced and contains over 80 expert labs with solutions for you to practise your new skills. To claim your 10 per cent discount on ANY course follow these steps: Go to https://training.linuxfoundation.org/linux-courses and browse the complete range of courses. Select the…

New features are being added to Gnome all the time. One of the latest ones, introduced in Gnome 3.24 is Night Light, which adjusts colour temperatures depending on the time of day and year. Having warmer temperatures outside of daylight hours can reduce eyestrain and tiredness. This functionality has been available through programs light RedShift, but it’s nice to see it as a bona fide Gnome feature now. Especially since RedShiftuses a legacy system tray icon, a habit which doesn’t match the Gnome vision. Gnome 3 also has a built-in screen recorder, just press Ctrl+Alt+Shift+R and a red dot will appear in the top-right corner, indicating recording is in progress. Use the same key combination to finish recording and the resulting cinematic masterpiece will be saved in the ~/ Videos…

There’s a reason users see this message when they enter sudothe first time around. The fact of the matter is that it’s true. Just because you can create a customised Arch Linux disc image and put it up on sourceforge and be featured in distrowatch, doesn’t always mean you should. You need to understand that people who download your ISO won’t have the same hardware that you might have tested it on. There will be bug reports, and people will ask for help using it. It takes time and effort to maintain a Linux distribution that’s been submitted to the general public for download. Some Linux distros rely entirely on donations to keep them running. If you do go down the road of uploading to sites like sourceforge, then we…

Our expert Mihalis Tsoukalos Mihalis is a UNIX administrator, mathematician programmer and DBA who enjoys writing articles. You can find him on Twitter: @mactsouk. By the end of this article you’ll know how to generate difficult-to-guess passwords in various programming languages. However, the main purpose of this tutorial is to get you involved into the process, make you think and perhaps even come up with a better solution than the ones presented here. Some programming languages might offer modules and packages that automatically generate good passwords. However, the problem is that they leave little space for learning, customisation and experimentation, which takes away the fun from the whole programming process. A forthcoming issue of Linux Format might include the code and the list of people who did well with the…

Our expert Mihalis Tsoukalos Mihalis is a UNIX administrator, mathematician programmer and DBA who enjoys writing articles. You can find him on Twitter: @mactsouk. This month’s Python exploration is all about the plotting of the digits of pi as an image, in this case in PNG format. However, this isn’t as simple as it seems, because you’ll need to know how to read and write to files, as well as how to specify the colour of a pixel in an image. To make things even more interesting, this tutorial will present full code examples in Python 3, Perl and Go. Additionally, you’ll see Julia and R code that enables you to read a text file character by character so that you can understand the differences between general-purpose languages and programming…

Although it’s now at version 12.1, Linux Format has have not included Zorin OS on our discs for several years, if ever. So let’s make up for it with the latest version of this distribution designed for those new to Linux. It has a simple interface that should be reasonably familiar to Windows users dipping their toes in the Linux waters for the first time, while still retaining all that makes Linux special. Easy to use doesn’t have to mean simplistic or limited, This is still a Linux distro at heart, just like all the others. Nothing has been taken away, but the user interface and default software choices are set up for those more used to Windows. Zorin takes a similar approach to elementary OS in providing a chosen…

The other two distros on this DVD are based on Ubuntu, but Manjaro is derived from Arch Linux. Arch is a bit of a power-user’s distro, so you may be surprised to see Manjaro being touted as suitable for new users – but it is! Manjaro offers a choice of desktops and the XFCE version is on offer this month. XFCE is a fast, reasonably lightweight, desktop that follows the more traditional desktop layout. That makes it an ideal choice for new users, unless they’ve only ever experienced Windows 8! Login: manjaro, password: manjaro…

Deploy the Zeta filesystem We take a long, hard look at what you need and how you can safely roll out the ZFS on all your systems. The Linux Multimedia Studio It’s time we made beautiful music together with the pro-level music creation suite known as LMMS. BSD vs Linux The biggest open source kernels go toe to toe, so we can finally decide which is the best for your server. Servers, servers, servers What’s the best business server to deploy? Stability, speed, features and more – we test a bunch for you. Contents of future issues subject to change – we might be having too much damn fun!…