Linux User & Developer 157 - Build Your Own System Tools

100 Pages·2015·24.146 MB·English

by  Gavin Thomas

EXCLUSIVE
PROJECT CODE, VIDEOS & SOFTWARE
www.linuxuser.co.uk
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001_LUD_157 Week3.indd 1 08/09/2015 17:51
Full Page.indd 1 02/09/2015 16:07
Welcome
Get
Linux User
to issue 157 of Linux User & Developer
cheaper
every issue
This issue
… Jon Masters is a Linux kernel hacker who has
been working on Linux for some Page 34
19 years, since he fi rst attended
s university at the age of 13. Jon lives » Launch a Docker container
in Cambridge, Massachusetts,
t and works for a large enterprise » Run Windows software in Wine
r Linux vendor. You can fi nd his
e brilliant Kernel Column on pages » Discover systems programming
16-17 this month.
p » Build a Raspberry Pi music visualiser
Richard Smedley has been helping businesses
x
and community organisations of all
e sizes to move to GNU/Linux since Welcome to the latest issue of Linux User &
the 1990s, and doesn’t expect those Developer, the UK and America’s favourite Linux
x he works with to share his love of
Emacs. Well, maybe a little. This and open source magazine.
u month he dives deep into Wine to This month we’re focusing on the developers
show us how we can run essential
n Windows software natively (p.28). among you: starting with a big guide to systems
programming in C that we’re going to follow with a
Li Liam Fraser is the creator of the run of tutorials over the coming months (page 20), we
RaspberryPiTutorials YouTube
series and volunteers as a Linux have some excellent guides that will get you started with C#
f
server administrator for the
o programming, Docker containers, automation and security
Raspberry Pi Foundation. Liam
combines his love of electronics on AWS, and a pair of tutorials on R and D3.js to help you
m and music in this issue, explaining
manipulate and visualise data. We’ll be revisiting some of
how to map audio to an LED strip for
real-time visualisation (p.62). these before the year is out, so stay tuned.
a
With Windows 10 raising all sorts of privacy concerns, it
e Mihalis Tsoukalos is a UNIX system
administrator with expertise in was also time to complement the guides to virtualisation and
t programming, databases and multibooting that we ran in previous issues with a third option
maths. He has been using Linux
r since 1993. Mihalis has been busy for giving you access to software that doesn’t play nicely on
u this month, creating some excellent Linux: Wine. Using this and PlayOnLinux, we show you how
guides to systems programming
o (p.20), R (p.36), D3.js (40), as well as to run things such as Photoshop and your PC games on your
Y this month’s Coding Column (p.11). favourite distro (page 28), so you can wash your hands of
Dan Aldred is a Raspberry Pi Certifi ed Educator Windows altogether and help your friends do the same.
and a Lead School teacher for CAS. As for the Ras Pi section, we’ve got something really special
He is passionate about creating and
for you. Remember the LED strip you used a couple months
hacking projects, and uses projects
like this to engage the students that back? Well, we’re turning it into a music visualiser (page 62).
he teaches. Turn to page 76 to fi nd
Plus, we show you how to text and tweet from your Pi – enjoy!
his simple guide to setting up Twilio
with your Raspberry Pi, so you can Gavin Thomas, Editor
send an SMS from the terminal.
Get in touch with the team:
Gareth Halfacree is our resident news
reporter and brings us the latest
developments from all over the [email protected]
open source world, starting over
on page 6. This month Gareth also
reviews the new Encryptr software, Buy online
which protects passwords and card Facebook: Twitter:
details using the zero-knowledge
Linux User & Developer @linuxusermag
Crypton framework (p.86).
Visit us online for more news, opinion, tutorials and reviews:
www.linuxuser.co.uk
www.linuxuser.co.uk 3
003_LUD_157.indd 3 09/09/2015 19:33
Contents
Reviews
81 GTD software
Find the best programs to support a
Getting Things Done methodology
Subscribe
& save! Todo.txt Freeplane GTD+
34s csu Suhbasosvtpoce mr p3ibr0eiec%r es .oc Uann Sth e
via page 60 mGSD Org-mode
20 Build your own system tools
Discover the power of systems programming 86 Encryptr
Zero-knowledge cloud storage for all of
your passwords, card details and notes
OpenSource Tutorials
06 News 36 Manipulate and convert data in R
T he biggest stories from the Transform your stored data sets easily
open source world
40 Visualise your data using D3.js
08 Free software column Create impressive, interactive displays with
Expert insights into open the Data-Driven Documents library
source and free software
44 Launch your first Docker container
11 Coding column Join the containers revolution today 88 Bodhi Linux 3.1.0
Learn problem solving and The Enlightened distribution moves
systems programming in C 48 Automate Linux on AWS across to the new Moksha desktop
Simplify your Amazon Web Services
12 Interview administration by setting up Spot Instances
Sebastian Kügler speaks
about Plasma Mobile 52 Secure access to your
AWS resources
16 Kernel column Keep data safe and your service operational
The latest on the Linux
kernel with Jon Masters 56 Start programming in C#
Learn to work with the MonoDevelop IDE
94 Letters and begin writing C# software
Your questions and views
FFiilleeSSiilloo..ccoo..uukk
Features
20 Build system tools
Five utilities to make now
61 Practical Raspberry Pi
28 Windows with Wine
Build the ultimate party piece, explore the
No VMs, no dual-booting ElectroSuper tunnel, set up a Samba hard
99996666 FFFrrreeeeee dddooowwwnnnllloooaaadddsss
drive for OSMC, learn to use the 1-Wire bus,
62 Pi music visualiser Find out what we’ve uploaded to our digital plus send texts and tweet from your Pi
Control LEDs with sound content hub FileSilo for you this month
Join us online for more Linux news, opinion and reviews www.linuxuser.co.uk
4
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Full Page.indd 1 02/09/2015 16:07
06 News & Opinion | 12 Interview | 90 Q&A | 94 Your Letters
ENTERPRISE
Linux Foundation announces
the Open Mainframe Project
Brings together industry and academic partners
The Linux Foundation has announced a project “Linux today is the fastest-growing operating The Open Mainframe Project is an offi cial Linux
in partnership with industry giants to advance system in the world. As mobile and cloud Foundation Collaborative Project and aims to
an enterprise-grade platform for Linux on computing become globally pervasive, new leverage the strengths of Linux in order to take
mainframe devices, unsurprisingly dubbed the levels of speed and efficiency are required in advantage of the unique features of mainframe
Open Mainframe Project. the enterprise and Linux on the mainframe is hardware. This includes the LinuxONE family,
The project brings together industry giants poised to deliver,” claimed Jim Zemlin, executive announced the same day by IBM and Canonical.
ADP, CA Technologies, IBM and SUSE as founding director at the Linux Foundation, at the project’s As well as industry members, several academic
platinum members, while BMC, Compuware, LC3, announcement. “The Open Mainframe Project will institutions have confirmed membership of the
RSM Partners and Vicom Infi nity join as silver- bring the best technology leaders together to work project, including the University of Bedfordshire.
level members. Its formation comes as industry on Linux and advanced technologies from across “This is an exciting time to be involved in
demand for mainframe systems resurges thanks the IT industry and academia to advance the most enterprise technologies. The potential benefits
ttoo iinntteerreesstt iinn cclloouudd ccoommppuuttiinngg aanndd bbiigg ddaattaa ttooppiiccss.. ccoommpplleexx eenntteerrpprriissee ooppeerraattiioonnss ooff oouurr ttiimmee..”” of open source systems optimised to run on
the mainframe’s highly scalable and reliable
architecture are very significant,” claimed Herbert
Daly, senior lecturer in computer science and
technology at the University. “The Open Mainframe
Project offers our staff and students a fantastic
opportunity to collaborate with an outstanding
field of talent, dedicated to shaping the future of
business-critical enterprise computing.”
One of the fi rst tasks for the Open Mainframe
Project is the establishment of a neutral home for
community meetings, events and collaborative
discussions, providing structure around the
business and technical governance of the project.
On a technical level, the group aims to broaden
the tools and resources that are intended to drive
development and collaboration of mainframe
Linux, while also coordinating mainframe
improvements to upstream projects. This is
in order to increase the quality of these code
submissions and ease upstream collaboration.
“Demand has grown among academic,
corporate and government partners for
furthering the mainframe’s expansion into the
open ecosystem,” claimed Ross Mauri from IBM.
“IBM looks forward to contributing our expertise
to the community and learning from others to fi nd
innovative ways to combine the fl exibility of open-
source software with the world-class speed,
security and scalability of the mainframe.”
Left Mainframes such as IBM’s z Systems drive
enterprise platforms and big data computing
006-011_LUD157.indd 6 09/09/2015 16:03
MAINFRAME TOP FIVE
Features in KDE
Plasma 5.4.0
1 Application Dashboard
A new full-screen menu, the Application
Dashboard, takes over from the Application Menu
with a focus on making full use of high-resolution
screens. This is in order to fi nd you your software
and fi les as quickly as possible, while including
easy keyboard navigation and type-to-search
functionality for the mouse-averse.
2 Wayland preview
The latest Plasma release brings the new kwayland-
integration repo, giving those who like to live on the
cutting edge a chance to play with the new Wayland
windowing system, without having to give up on their
existing KDE framework integration.
IBM and Canonical 3 Network applet graph
If you would like to keep an eye on historical network
traffi c, you will be pleased to know that a new graph
launch LinuxONE
is set to appear in the network applet. The applet
also gains SSH and SSTP VPN support via two new
default plugins.
4 Easy monitor calibration
Mainframe includes custom Ubuntu distribution
The gamma monitor calibration tool is new to KDE
Plasma 5.4.0 and offers an easy way to adjust how
IBM and Canonical have jointly announced the capabilities of commodity servers that are colours are reproduced on your display, providing
launch of a new Linux-powered mainframe not designed for security and performance at either print colour matching or simple adjustments
family, the IBM LinuxONE, featuring a variant of extreme scale.” to your personal preference.
Canonical’s Ubuntu Linux distribution. IBM has also pledged to provide open access 5 New icons galore!
Announced on the same day that IBM joined the to the LinuxONE platform with the launch of a
Open Mainframe Project as a founding member, developer cloud platform. Hosted at academic For those who like a bit of eye candy, the news
the LinuxONE family is based on IBM’s z Systems institutions as well as IBM facilities in Dallas, that KDE Plasma 5.4.0 includes 1,400 new icons
platform and launches in two flavours. Firstly, Beijing and Böblingen, instances will enable free providing Breeze-themed artwork, covering
a range of applications and services, will be
the top-end IBM z13-based LinuxONE Emperor, trials and educational access at no charge.
welcomed. These include such apps as Inkscape,
offering a claimed ability to run up to 8,000 virtual “The largest enterprises in the world count
Firefox and LibreOffi ce.
machines simultaneously. Secondly, a scaled- on Ubuntu as their platform for scale-out
down variant dubbed the LinuxONE Rockhopper, applications, private and public clouds. With the
designed for entry-level mainframe users. expansion of Ubuntu support to IBM z Systems
“Fifteen years ago, IBM surprised the industry and LinuxONE, IBM mainframe customers will
by putting Linux on the mainframe, and today benefi t from Ubuntu’s ecosystem of scale-out
more than a third of IBM mainframe clients are and cloud solutions,” boasted Canonical’s Jane
running Linux,” claimed Tom Rosamilia, enior Silber of the partnership. “IBM and Canonical
vice president of IBM’s Systems division. “We teaming to bring Ubuntu to z Systems allows
are deepening our commitment to the open customers to leverage the speed and security of z
source community by combining the best of the Systems, and the open source software and tools
open world with the most advanced system in of Ubuntu, to enhance the IT operations for a new
the world, in order to help clients embrace new universe of customers.”
mobile and hybrid cloud workloads. Building Both LinuxONE mainframe models are
Above The Visual Design Group is working to
on the success of Linux on the mainframe, available to order from IBM now, with pricing expand the standard icon set to integrate the
we continue to push the limits beyond the provided by the company upon request. Breeze, Breeze Dark and Oxygen variants
www.linuxuser.co.uk 7
006-011_LUD157.indd 7 09/09/2015 16:03
OpenSource
Your source of Linux news & views
OpiniOn frEE SOfTWArE
Software communes
The contribution of the free software movement, both in ideas and
hard code, to the rise of Linux isn’t always given its due recognition
October is the 30th anniversary of reassign the rights to the user. The irst tangible version
the founding of the Free Software of such a licensing regime was ‘the GNU Emacs copying
Foundation, a moment that was permission notice’ in 1985, although the GPL as we know
barely noticed in its time but can be said to have it irst appeared in 1989. The GPL and its preamble were
transformed the development of software. The the most complete expression of the principles of free
concepts that deine free software grew out of richard software, but the moment that made free software a
Stallman’s experiences at the AI Labs at MIT, his concept to be reckoned with was the release of the Linux
personal history with the development of the LISP kernel. Linux had been developed using the GNU tools
machine and his disputes with James Gosling over the and was licensed under the GPL.
licensing of Emacs. As early as October 1981, Stallman Linus Torvalds later said that “making Linux GPL’d
had written: “Emacs does not cost anything; instead, was deinitely the best thing I ever did”. The informality
you are joining the Emacs software-sharing commune. of the model that grew around GNU/Linux and the
The conditions of membership are that you must send GPL gave everybody the chance to take part and
back any improvements you make to Emacs, including make a difference. You could do anything with Linux,
any libraries you write…”, which could be seen as an bash it to pieces, install it on your virtual fridge or
early attempt to deine copyleft and the irst principles washing machine, shake it or break it, create your own
Richard Hillesley
of the free software movement. distribution and share it with the world. If you couldn’t
James Gosling, who was later famous for the writes about art, music, digital write code, you could write documentation, host
rights, Linux and free software for
development of Java, wrote a version of Emacs, derived a variety of publications websites, make friends or sell t-shirts.
from Stallman’s original concept of Emacs, in C for Unix. This surprising effect extended to the commercial
According to Stallman, he “seemed to be inluenced world. Once more, as one hardware company had
by the same spirit of sharing and cooperation of the formed a commitment to Linux, it became obvious that
original Emacs… He wrote in a manual that he called the there was a mutual advantage in contributing back to
program Emacs hoping that others in the community The informality the project and they did. The framework that made this
would improve it until it was worthy of that name.” possible was the GPL. The release of core chunks of
of the model
Gosling initially enabled free distribution of the source corporate code accelerated the development of Linux
code, to which others had contributed, and Stallman that grew around and ensured its success in the enterprise, enhanced
incorporated some of the code in early versions of GNU by its portability across a wide range of hardware.
GNU/Linux and
Emacs, but in April 1983, according to Stallman, “he The GPL encouraged commoditisation, and at the
stabbed everyone in the back by putting copyrights on the GPL gave system level, commoditisation reduced the costs and
it, making people promise not to redistribute it, and then subsequently beneitted everybody.
everybody the
selling it to a software-house.” Commoditisation of the operating system ensures
Gosling had sold GOSMACS, his version of Emacs, to chance to take commoditisation of standards. This makes it easier
UniPress and quasi-legal threats were made against to port software between different machines and
Stallman. When GNU Emacs was released in the year part and make a architectures, and makes it easier to design hardware
1985, Unipress announced that “portions of the GNU difference itself. Companies don’t use GNU/Linux because of
Emacs program are most deinitely not public domain, sentimental attachment to Linux or the GPL, or “open
and that use and/or distribution of the GNU Emacs source”. They use GNU/Linux and free software
program is not necessarily proper.” because it makes business sense. And free software,
Stallman rewrote the offending sections of GNU guaranteed by the GPL, gave assurance of the
Emacs, but the confrontations with Gosling and continued freedom and commonality of the code. The
Unipress had convinced him that public domain was contribution of the free software movement, both in
not suficient to protect the rights of free software. ideas and hard code, to the rise of Linux isn’t always
Stallman’s solution was to invert copyright law and given the recognition it deserves.
8
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ROUTERS
FCC threatens to block
custom router fi rmware
New software-defi ned radio rules could
spell trouble for enthusiasts
The ease with which wireless network routers Replacing the stock firmware of Linux-based Above Devices like the Linksys WRT1900AC
can be modified with a third-party firmware is networking hardware with more powerful third- could become illegal under new FCC rules
set to take a hit thanks to new rules from the party alternatives, such as OpenWRT, is popular
US Federal Communications Commission that enough that there are router models designed with he claimed, “this change does not only affect
promise to block firmware modifications. this specifically in mind. However, under the new routers in the US, but also Europe, and this will also
Under rules that became effective this year, set FCC Part 15 rules, they could become illegal in the affect wireless communities.”
to be fully enforced for all devices on the market in US over fears that they could be used to operate in As well as unlocking new features, third-party
June 2016, the FCC is to require all licensed devices unlicensed spectrum, or at illegal power levels. firmware is often used to breathe new life into
– a requirement for sale in the US – to “implement Speaking at the Wireless Battle of the Mesh devices that manufacturers have ceased to
software security to ensure that the devices event in Slovenia, Simon Wunderlich argued that support. This means that under the new rules,
operate as authorised and cannot be modified,” this was likely to have a global impact. “Since the consumers could be left running insecure devices
seemingly to lock out third-party modifications. same types of devices are often sold worldwide,” on their network due to the new restrictions.
STORAGE
Kinetic is now an
open Linux project
Seagate’s enterprise-grade storage platform, Kinetic, is now an official
Linux Foundation Collaborative project, with companies including
Western Digital, Toshiba, Dell and Cisco joining the development effort.
Kinetic combines storage devices featuring integrated Ethernet
connectivity with a key/value store paradigm claimed to improve the
effi ciency, scalability and fl exibility of enterprise storage.
Using open source software and a standardised set of application ADD A REMOTE
programming interfaces (APIs), storage developers can use a Kinetic
DBA TO YOUR TEAM
system to reduce the overheads of storage area network (SAN)
implementations, taking advantage of features like direct drive-to-drive
data transfer via Ethernet, without needing an intermediate host device.
Although billed as the Kinetic Open Storage platform, the standard
remained under Seagate’s control until the formation of the Linux
Remote DBA from 2ndQuadrant is
Foundation Collaborative Project. Now truly open, network and storage
the ideal solution for organisations
vendors have joined and pledged their support, but none have offered a
release date for Kinetic-compatible, Ethernet-enabled storage devices. needing extra help to manage their
According to documentation, Kinetic enables an increase in rack PostgreSQL database – with our
density, a reduction in power draw and cooling, easy data sharing, and expert knowledge of the core code,
the removal of what the company calls “superfl uous layers of legacy you couldn't be in safer hands
software and hardware” associated with traditional SAN platforms.
“The Seagate Kinetic Storage platform… delivers the new paradigm
necessary to enable us collectively, as an industry, not only to meet this
Remote DBA is offered as a service extension to our
mandate, but to do so optimally and in the most cost-effi cient manner Gold and Platinum Production Support service plans
required,” a company spokesman claimed at the announcement.
UK [phone]
US [phone]
2ndquadrant.com/rdba
006-011_LUD157.indd 9 09/09/2015 16:03
OpenSource
Your source of Linux news & views
DISTRO FEED
Top 10
(Average hits per day, 5 August - 3 September)

Linux Mint
1. 3,096
Debian
2. 2,062
Ubuntu
3. 1,569
GAMING
openSUSE
4. - 1,175
5. Fedora 1,148 Unity game
Manjaro
6. 1,123
CentOS
7. 981 engine hits Linux
Mageia
8. 945
Kali Linux
9. 925
Zorin OS
10. 800
Future support for the platform is not guaranteed
This month
The game engine specialist Unity has call an experimental build; future support is
announced the release of an experimental not yet guaranteed,” warned Unity’s Na’Tosha
■ Stable releases (24)
■ In development (13) build of its software for Linux, making good on Bard. “Your adoption and feedback will help us
its roadmap promise to support the operating determine if this is something we can sustain
While Linux Mint has system in future releases. alongside our Mac and Windows builds.” Bard
taken a hit, it remains A popular engine for both games and general- did not indicate what usage and feedback levels
number one. Meanwhile,
purpose 3D rendering, Unity has previously been would constitute enough for the company to
Kali’s rise to the top ten
is rare for an application- restricted to use on only proprietary platforms. adopt Linux as a fully supported platform for all
specifi c distro This month’s release changes that, bringing future releases, following in the footsteps of rivals
offi cial support for running the software on including Epic’s Unreal Engine.
Highlights Ubuntu 12.04 or newer, plus unoffi cial support for Interest from developers in Linux as a gaming
other 64-bit Linux distributions. platform is higher than ever, thanks in no small
The release is a test for the company, part to game developer and publishing giant
Ubuntu 15.10 Beta 1 however, and Unity has not committed to a full Valve basing its gaming-centric operating system
Released ahead of the full launch and formal release. “Today’s build is what we SteamOS on the Debian Linux distribution.
in October, the latest Ubuntu ‘Wily
Werewolf’ beta comes in standard, Kubuntu,
FEDORA
Lubuntu, Ubuntu GNOME, Ubuntu MATE, Ubuntu
Kylin, Xubuntu and Ubuntu Cloud fl avours for
testers of every type to enjoy. Support for 32-bit x86 demoted
Zorin OS 10
Featuring an Ubuntu 15.04 base, the latest Fedora makes 64-bit x86 the gold standard
Zorin OS includes a new media player and a
neat activity journal that displays files and documents
you have worked on throughout the day. The Fedora project has demoted support for 32- After some discussion, the committee
bit x86 architectures from its Linux distribution, agreed to change the vote away from a total
Kali 2.0
following a vote by the Fedora Engineering abandonment of i686 support, to making it a
The release of Kali 2.0 has brought a shift Steering Committee (FESCo). non-blocking deliverable. This means that its
to a rolling-release model. It is designed
In its late August meeting, FESCo raised a absence (should work not be complete in time)
to make it easier to keep the penetration testing and
vote on removing support for the i686 32-bit would not prevent the general launch of Fedora
security distribution updated.
x86 instruction set architecture from Fedora 24, effectively demoting the architecture support.
24. “From my PoV [point of view], nobody wants The 64-bit x86 architecture, backwards-
Latest distros to support the i686 image,” Haïkel Guémar told compatible with the traditional 32-bit variant, was
available: attendees. “I’m completely +1 for [in favour of] launched in 2003 by AMD as AMD64 and picked
dropping all of the i686 images/media in f24 up by Intel a year later. Today, the majority of both
fi lesilo.co.uk [Fedora 24],” added Kevin Fenzi. company’s chips are 64-bit.
10
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