Issue #224 / Jul 2019

DVD: Ubuntu 19.04 and Fedora 30

Article Code

Approximate on sale dates:

  • UK/Europe: Jun 01
  • USA/Canada: Jun 28
  • Australia: Jul 29


Energy efficiency studies often focus on hardware, but what about the software? As it turns out, software tools created for similar tasks sometimes use energy very differently. Also in this month's issue:

  • Barrier -- declutter your desk with a free tool that lets you operate multiple computers with one keyboard and one mouse.
  • Network Analysis -- Search for intruders with tcpdump, Wireshark, and NetFlow.

Check out MakerSpace for a look at malware analysis on the Raspberry Pi, as well as a study of Amazon's Greengrass IoT services. This month in Linux Voice, we highlight some unsung command-line tools and explore some useful LibreOffice extensions.

SERVICE: Welcome

Small Crack in the Garden Wall

A news story is breaking as we send this issue to press, and since this column is always the last thing I do, I find myself with a quiet moment to reflect.

SERVICE: This Month's DVD

Ubuntu 19.04 "Disco Dingo" Desktop and Fedora 30 Workstation

NEWS: News

Updates on technologies, trends, and tools

Fedora Project announces Fedora 30; the Apache Software Foundation completes migration to GitHub; Canonical combines its services in a single package; Black Hole Image has an open source connection; Ubuntu 19.04 released; Linux Mint founder calls for better developer support; and VMware patches critical vulnerabilities.

NEWS: Kernel News

Improving the Android low memory killer; randomizing the Kernel stack; and best practices.

: Energy Study

Evaluating the environmental impact of software

It's getting easier to measure the environmental impact of software. A new study suggests criteria for determining how the choice of software impacts resource use.

REVIEWS: Image Viewers

Comparing image viewers for photographers

For today's photographers, image viewer programs are an essential piece of equipment, because they can help you quickly load and sort your photo and video files. We compare some of the top image viewers.

IN-DEPTH: Fly on the Wall

Troubleshooting HTTPS connections with mitmproxy

Finding the data zipping back and forth between the browser and server is not only interesting for snooping spies, but also for debugging developers. Mike Schilli gets you started with mitmproxy and shows how to customize it using Python scripts.

IN-DEPTH: Simple Security

File encryption with EncFS

EncFS is an easy and effective CLI application for encrypting files that also allows for customization.

IN-DEPTH: The sys admin's daily grind: Tiger VNC

Big Cat to the Rescue

Sys admin columnist Charly enumerates the computers in his household and makes it clear that commuting between them would be an unreasonable burden on his personal energy balance. Instead he lets a tiger go the distance for him.

IN-DEPTH: Barrier

Share input devices between computers with Barrier

Barrier is a Synergy fork that lets you work with one keyboard and mouse pair on multiple Linux, Mac OS X, or Windows computers.

IN-DEPTH: Network Analysis

A study in detecting network intruders

The nightmare of any admin is a user who can't resisting clicking on an unknown attachment labeled Application.exe. This article draws on a real-world example to show how you can use built-in Linux resources to detect unauthorized traffic that might have been invited in by a trigger-happy user.

: Rasp Pi Security

Analyzing a malicious Raspberry Pi Bash script

Analyze malware on hacked Raspberry Pis and create a signature to detect malware in log entries.

: Greengrass

Raspberry Pi on the IoT

The Amazon Web Services command-line interface and the Amazon Greengrass IoT Core services read and merge Raspberry Pi sensor data.

NEWS: Goodbye eelo, Hello /e/

Update on a new free phone

With a name change, Gaël Duval's quest for a free phone with supporting infrastructure rapidly moves ahead.

LINUX VOICE: Introduction


This month in Linux Voice.

LINUX VOICE: 10 LibreOffice Extensions

Ten useful LibreOffice extensions

LibreOffice has hundreds of options and features, but these handy extensions make it even more convenient.


One weekend this month, Graham's synth obsession took him 600 miles in a rental car into ancient Cornwall to buy a beat-up old 1980s MIDIBoard. Stay tuned for a Linux editor! Graham looks at Surge, fd, Kloak keystroke anonymizer, Symphytum, uMatrix,†and more!

LINUX VOICE: Bash Functions

Organizing and reusing Bash code

Learn how to make your Bash code more readable, robust, and reusable by managing the code within your Bash scripts.

LINUX VOICE: Mother of Invention

Technical 3D design using FreeCAD

Designing simple shapes in OpenSCAD is easy, but if you want to print complex machines with multiple interlocking pieces, you need to bring out the big guns. That's where FreeCAD comes in handy.

Issue 224/2019

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