Terminal Zero: Building the Ultimate Raspberry Pi Zero Computer

The new edition has no keyboard in favor of a touchscreen interface. The case is custom designed and no only has a huge selection of ports to access but also additional buttons. The unit is completely wireless, using a LiPo battery for power. There's a small speaker inside but you can also use headphones via a 3.5mm jack.

Will This Speed up Your Raspberry Pi Browsing by up to 1200%?

Puffin manages these incredible speeds because the content is rendered remotely on their encrypted cloud servers. A JavaScript engine is used to pre-process and compress web pages before they arrive at your screen. This can be interpreted as a proxy server by some sites, and may affect the content that is available to you.

Odroid H2 as ventilator cooling ventilation airmachine

finally summer and climate change have both reached Europe and had several weeks of 30 C straight… without ventilation, anything above 30 is just “too much to think” (so maybe the brain CPU also would need active cooling?) of course the user could buy a fan online… or try to use CPU fans to do the job

Track your punches with Raspberry Pi

Garage Minder

A Raspberry Pi Zero W is used to open and close the garage door. I did not have a convenient outlet to plug in a power supply for the Pi. So my Pi gets its power from the existing garage opener control wiring for the wall button. Typically, there is 24 volt AC available here, though it may be a lower voltage in older openers. A Buck converter down-regulates this voltage to 5 v DC. A battery allows the Pi to continue when the wall button is momentarily pressed, and the power is shorted out. We need two diodes so that the forward drop (1.4v) stops the 6v battery from continuously discharging into the 5v power supply. The battery is barely used, so it should last for a long time. If an outlet is conveniently available, then a regular 5v micro USB charger can be used.

Go filesystems and file embedding

The Go team has recently published several draft designs that propose changes to the language, standard library, and tooling: we covered the one on generics back in June. Last week, the Go team published two draft designs related to files: one for a new read-only filesystem interface, which specifies a minimal interface for filesystems, and a second design that proposes a standard way to embed files into Go binaries (by building on the filesystem interface). Embedding files into Go binaries is intended to simplify deployments by including all of a program's resources in a single binary; the filesystem interface design was drafted primarily as a building block for that. There has been a lot of discussion on the draft designs, which has been generally positive, but there are some significant concerns. Russ Cox, technical lead of the Go team, and Rob Pike, one of the creators of Go, are the authors of the design for the filesystem interface. Cox is also an author of the design for file embedding along with longtime Go contributor Brad Fitzpatrick. Additionally, Cox created YouTube video presentations of each design for those who prefer that format (the filesystem interface video and the file-embedding video).

a Piece of Note on Unicode Encoding for CJK characters (with my simple Caesar encoding script)

Plasmoid with C++

So the goal is pretty simple, and all I have to do is to find a way to share information from KClock to the plasmoid. However the solution isn’t that trivia. As it turned out, DBus is perferred for IPC(Inter-process communication). Before start working on plasmoid, I need to expose some of the class of KClock to DBus first. Since KClock is built upon Qt, I choose to using Q-DBus as it will save a lot of effort than using low level interface. Now the problem is - I don’t know how to use Q-DBus. As usual, I went to the Qt documentation and to my surprise, it spent most content to describe the concept of DBus and compared to Qt’s signal/slot machinism. Although useful as it is, lack of examples meaning I still didn’t know how I can use it in my code. Thankfully, KDE has its own tutorial about DBus and it provides multiple examples. You can find it here.

How to use printf to format output

When I started learning Unix, I was introduced to the echo command pretty early in the process. Likewise, my initial Python lesson involved the print function. Picking up C++ and Java introduced me to cout and systemout. It seemed every language proudly had a convenient one-line method of producing output and advertised it like it was going out of style.

Ceph – the practical storage solution for companies of all sizes

Ceph was conceived by Sage A. Weil, who developed it while writing his dissertation and published it in 2006. He then led the project with his company Intank Storage. In 2014, the company was acquired by RedHat, with Weil staying on as the chief architect, in charge of the software’s development.

Ceph only works on Linux systems, for example CentOS, Debian, Fedora, RedHat/RHEL, OpenSUSE, and Ubuntu. Accessing the software through Windows systems cannot be done directly, but is possible through the use of iSCSI (Internet Small Computer System Interface). As such, Ceph is particularly suitable for use in data centers that make their storage space available over servers, and for cloud solutions of any kind that use software to provide storage.

We have complied a list of the most important features of Ceph: [...]

"Structural pattern matching" for Python, part 1

We last looked at the idea of a Python "match" or "switch" statement back in 2016, but it is something that has been circulating in the Python community both before and since that coverage. In June it was raised again, with a Python Enhancement Proposal (PEP) supporting it: PEP 622 ("Structural Pattern Matching"). As that title would imply, the match statement proposed in the PEP is actually a pattern-matching construct with many uses. While it may superficially resemble the C switch statement, a Python match would do far more than simply choose a chunk of code to execute based on the value of an expression.

Federico Mena-Quintero: "Rust does not have a stable ABI"

These are extremely valid concerns to be addressed by people like myself who propose that chunks of infrastructural libraries should be done in Rust. So, let's begin. The first part of this article is a super-quick introduction to shared libraries and how Linux distributions use them. If you already know those things, feel free to skip to the "Rust does not have a stable ABI" section.

Checking out FreeCAD

Our look at running a CNC milling machine using open-source software led me to another tool worth looking at: FreeCAD. I wasn't previously familiar with the program, so I decided to check it out. In this article I will walk through my experiences with using FreeCAD for the first time to do a variety of CNC-related tasks I normally would have used a commercial product for. I had varying degrees of success in my endeavors, but in the end came away with a positive opinion. FreeCAD is an LGPL v2+ licensed CAD and CAM program written in Python and C++. The first release of the project was in 2002, and its last stable version 0.18.4 was released in October 2019. The project's GitHub page indicates that it has 271 contributors with new commits happening often (generally more than 50 a week). Beyond code contributions, FreeCAD has a welcoming community with active forums to answer any questions users might have along the way. FreeCAD is designed to be cross-platform, supporting Linux, macOS, and Windows, with binary releases provided by the OS-independent package and environment management system Conda. I decided to take on a relatively simple CNC project: milling a new street-address sign for my home. The plan called for a 700mm x 150mm sign, and I decided to mill it out of a plank of maple wood. The design I have in mind is pretty straightforward, so it should be a great way to put FreeCAD through a test on a real project. I also looked at using FreeCAD for taking existing models that are available online with an open license and importing them for milling (in this case, a wooden spoon). It is worth noting that before this effort I had never used FreeCAD before. My personal goal is to become fluent enough with FreeCAD that I can replace my dependence on the commercial CAD software I presently use in my design work. The goal of this article, however, is to share what my experience with FreeCAD was, and provide a glimpse of FreeCAD from the perspective of an inexperienced user.

9 Best Emacs-Like Text Editors

Over the years, one of the most emotive areas in the world of Linux is the choice of text editor. Some people are strong advocates of Vim, others prefer Emacs. And there’s tons of other text editors available with strong backing. Having robust opinions is the way the land lies in Linux. Emacs has a long and revered history. The original program was written in 1976 as a set of macros for an existing text editor called TECO. Emacs originally was an acronym for Editor MACroS, unifying the many TECO command sets and key bindings. TECO is both a character-oriented text editor and an interpreted programming language for text manipulation. Emacs has come a long way since 1976. It offers a robust Lisp interpreter that is hugely extensible and hackable. It brought to light lots of novel concepts such as an infinite clipboard, tree-based exploration of history, a reverse variable search, structural editing of code, and recursive editing that let you stop what you are doing, perform other edits, and then revert back to the original task. Emacs is an incremental programming environment, a mutable environment that provides functionality without applications.

Michael Kerrisk (manpages): man-pages-5.08 is released

I've released man-pages-5.08. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org. This release resulted from patches, bug reports, reviews, and comments from more than 30 contributors. The release includes more than 190 commits that change around 340 pages.

QGIS has chosen Kiwi TCMS

We are happy to announce that QGIS has chosen Kiwi TCMS for the basis of their Quality Assurance methodology and infrastructure improvement program! Kiwi TCMS will play a central role in storing test case definitions, organizing test cycles, and assigning and tracking test executions by testers from the QGIS community.

Netgpu and the hazards of proprietary kernel modules

On its face, the netgpu patch set appears to add a useful feature: the ability to copy network data directly between a network adapter and a GPU without moving it through the host CPU. This patch set has quickly become an example of how not to get work into the kernel, though; it has no chance of being merged in anything like its current form and has created a backlash designed to keep modules like it from ever working in mainline kernels. It all comes down to one fundamental mistake: basing kernel work on a proprietary kernel module. The use case for netgpu appears to be machine-learning applications that consume large amounts of data. The processing of this data is offloaded to a GPU for performance reasons. That GPU must be fed a stream of data, though, that comes from elsewhere on the network; this data follows the usual path of first being read into main memory, then written out to the GPU. The extra copy hurts, as does the memory-bus traffic and the CPU time needed to manage this data movement. This overhead could be significantly reduced if the network adapter were to write the data directly into the GPU's memory, which is accessible via the PCI bus. A suitably capable network adapter could place packet data in GPU memory while writing packet headers to normal host memory; that allows the kernel's network stack to do the protocol processing as usual. The netgpu patch exists to support this mode of operation, seemingly yielding improved performance at the cost of losing some functionality; anything that requires looking at the packet payload is going to be hard to support if that data is routed directly to GPU memory.

Some statistics from the 5.8 kernel cycle

Linus Torvalds released the 5.8 kernel on August 2, concluding another nine-week development cycle. By the time the work was done, 16,306 non-merge changesets had been pulled into the mainline repository for this release. That happens to be a record, beating the previous record holder (4.9, released in December 2016) by 92 changesets. It was, in other words, a busy development cycle. It's time for our traditional look into where that work came from to see what might be learned. A total of 1,991 developers contributed to 5.8, which is another record; 304 of those developers appeared for the first time in this cycle. The community added over 924,000 lines of code and removed around 371,000 for a net growth of over 553,000 lines of code.

FUSE Read/Write Passthrough Updated For Much Better File-System Performance

Of various criticisms around FUSE for implementing file-systems in user-space, one of the most prolific issues is around the performance generally being much lower than a proper file-system kernel driver. But with the FUSE passthrough functionality that continue to be worked on, there is the potential for much better FUSE file-system performance. The ongoing FUSE passthrough work is about allowing the passthrough read/write of files in avoiding at times unnecessary overhead of the user-space FUSE daemon. When operating in FUSE_PASSTHROUGH mode, the daemon can allow on a per-file basis opening in passthrough mode where all read and write operations are forwarded by the kernel directly to the lower file-system rather than to the FUSE daemon running in user-space.

Navi 2 Fixes, Other Graphics/Display Fixes Sent In For Linux 5.9

Following all of the feature updates to the open-source GPU/DRM drivers for Linux 5.9 that included a lot of new material, the first batch of fixes have now been sent in for mainline in addressing early fallout from these many changes. Ahead of the Linux 5.9-rc1 release this weekend, an initial batch of Direct Rendering Manager fixes were sent out on Thursday.

How the ARM32 Linux kernel decompresses

This is intended as a comprehensive rundown of how the Linux kernel self-decompresses on ARM 32-bit legacy systems. All machines under arch/arm/* uses this method if they are booted using a compressed kernel, and most of them are using compressed kernels.

Walleij: How the ARM32 Linux kernel decompresses

For those who are into the details: here is a step-by-step guide through the process of decompressing an Arm kernel and getting ready to boot from Linus Walleij.