Rust Compiler April Steering Cycle

On Friday, April 9th, the Rust Compiler team had a planning meeting for the April steering cycle.

Every fourth Friday, the Rust compiler team decides how it is going to use its scheduled steering and design meeting time over the next three Fridays.

Oil Shell 0.8.9 Is Released

Oil Shell is a not-really drop-in replacement for Bash with its own programming language for "serious" shell programming. The latest release has some very minor changes to the oil-language and that's about it. It may be worth a look if you want a shell language where you can use variables without quotes.

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You can take a look at the "Oil Language Idioms" for examples of how regular bash compares to oil and acquire the technology from http://www.oilshell.org/releases.html if you want to see how it works. None of the GNU/Linux distributions we looked at have OSH in their repositories, so you will have to compile it yourself. It is a quick and small compile with nearly no dependencies, so you'll have it up and running in less than a minute.

Twine the easiest game engine for non-coder

In this article, we will give you a short introduction to a wonderful open-source tool called Twine that allows you to write your own interactive stories easily. What it is, why we should use it, we will recommend a tutorial and more.

Stupid RCU Tricks: rcutorture fails to find an RCU bug

If you are running a kernel built with CONFIG_PREEMPT=y, RCU read-side critical sections can be preempted by higher-priority tasks, regardless of whether these tasks are executing kernel or userspace code. If there are enough higher-priority tasks, and especially if someone has foolishly disabled realtime throttling, these RCU read-side critical sections might remain preempted for a good long time. And as long as they remain preempted, RCU grace periods cannot complete. And if RCU grace periods cannot complete, your system has an OOM in its future.

This is where RCU priority boosting comes in, at least in kernels built with CONFIG_RCU_BOOST=y. If a given grace period is blocked only by preempted RCU read-side critical sections, and that grace period is at least 500 milliseconds old (this timeout can be adjusted using the RCU_BOOST_DELAY Kconfig option), then RCU starts boosting the priority of these RCU readers to the level specified by the rcutree.kthread_prio kernel boot parameter, which defaults to FIFO priority 2. RCU does this using one rcub kthread per rcu_node structure. Given a default Kconfig, this works out to one rcub kthread per 16 CPUs.

Single-shot signal/slot connections

Sometimes it’s useful to establish a connection between a signal and a slot that should be activated only once. This is not how signal/slot connections normally behave.

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The static_cast isn’t technically necessary, in this case. But it becomes necessary, should we want to also pass some other arguments (for instance, if we want the connection to be queued as well as single-shot). This closed a long-standing and very voted feature request. Sometimes, by removing the pebble in your shoe, you make many other people happy.

The 10 Best Agile Frameworks: Choosing The Right Framework For You

Agile software development is a methodology related to application development focusing on an iterative process, where cross-functional teams collaborate to produce better solutions. Agile frameworks are unique methods or techniques in the development process following Agile principles. Most companies use these frameworks to mitigate their particular needs. Many popular Agile frameworks are available in the market. Different businesses utilize them according to their specific needs. It is significant for the product’s success to embrace a solid framework that aligns with the team’s requirements. That’s where we come in. Today we will help you to choose an Agile framework that matches your team requirements.

Niko Matsakis: Async Vision Doc Writing Sessions V

This is an exciting week for the vision doc! As of this week, we are starting to draft “shiny future” stories, and we would like your help! (We are also still working on status quo stories, so there is no need to stop working on those.) There will be a blog post coming out on the main Rust blog soon with all the details, but you can go to the “How to vision: Shiny future” page now.

What exactly was the point of [ “x$var” = “xval” ]?

The x-hack was indeed useful and effective against several real and practical problems in multiple shells.

However, the value was mostly gone by the mid-to-late 1990s, and the few remaining issues were cleaned up before 2010 — shockingly late, but still over a decade ago.

The last one managed to stay until 2015, but only in the very specific case of comparing opening parenthesis to a closed parenthesis in one specific non-system shell.

I think it’s time to retire this idiom, and ShellCheck now offers a style suggestion by default.

Rakudo Weekly News: 2021.15 First Conf

Andrew Shitov has announced the very first Raku Conference, to be held online on 7 August 2021. You can sign up if you want to attend, or want to give a presentation. Formats for presentations vary from a 5-minute lightning talk to an 8-hour workshop. The deadline for talk submissions is 15 July 2021. Of course, you can also sponsor this conference in various ways! Exciting to see our first Raku Conference planned like that!

Perl Weekly Challenge 108: Locate Memory and Bell Numbers

In languages such as Perl and C, it is a fairly common task to take a reference or a pointer to a variable, and a reference or a pointer are essentially the memory addresses of such a variable (for some definition of memory address). In Raku, using the memory address of a variable is almost never necessary (except possibly for low-level debugging purpose). Actually, I originally wasn’t even completely sure I was going to find a way of doing that in Raku. However, the Metaobject Protocol (MOP) offers some metamethods, which are introspective macros that provide information about objects (including variables). One such metamethod is WHERE, which returns an Int representing the memory address of the object.

Logica: organizing your data queries, making them universally reusable and fun

We present Logica, a novel open source Logic Programming language. A successor to Yedalog (a language developed at Google earlier) it is a Datalog-like logic programming language. Logica code compiles to SQL and runs on Google BigQuery (with experimental support for PostgreSQL and SQLite), but it is much more concise and supports the clean and reusable abstraction mechanisms that SQL lacks. It supports modules and imports, it can be used from an interactive Python notebook and it even makes testing your queries natural and easy.

Google Talks Up Logica As Open-Source Programming Language For Data Manipulation - Phoronix

Google engineers are responsible for a number of programming languages like Go and Dart while their newest one to be made public is Logica.

Logica is the successor to Yedalog, another language out of Google. Logica compiles to SQL and can run on Google BigQuery with experimental support for PostgreSQL and SQLite databases.

Make Conway's Game of Life in WebAssembly | Opensource.com

Conway's Game of Life is a popular programming exercise to create a cellular automaton, a system that consists of an infinite grid of cells. You don't play the game in the traditional sense; in fact, it is sometimes referred to as a game for zero players.

Once you start the Game of Life, the game plays itself to multiply and sustain "life." In the game, digital cells representing lifeforms are allowed to change states as defined by a set of rules. When the rules are applied to cells through multiple iterations, they exhibit complex behavior and interesting patterns.

12 Backend Development Tools For Web Developers

While Frontend Web Development is concerned with the designing of the user interface of the website using web technologies like HTML, CSS, JavaScript, etc. – Backend Web Development (or you can say Server-Side Development) is responsible for the appropriate functioning of the website.

Eclipse Foundation aims open VS Code registry at Microsoft

VS Code)extension users and providers argue that the industry needs a fully open source marketplace for the extensions. That's because Microsoft forbids the use of its marketplace for non-Microsoft-branded products, as noted in the marketplace user agreement, which reads: "Marketplace Offerings are intended for use only with Visual Studio Products and Services and you may only install and use Marketplace Offerings with Visual Studio Products and Services."

5 dead programming languages we should never forget [Ed: Many programming languages that Chris Tozzi called "dead" are not dead at all! Is he trying to bury things alive?]

Just as some spoken languages have faded into history, programming languages also face the risk of obsolescence and extinction. Though their profound influence on development techniques and coding styles certainly still resonates, languages like ALGOL and LISP don't enjoy nearly as much prominence and acclaim as they once did. It's only natural that some of the languages we use today will follow the same path.

In no way does that mean these languages will disappear entirely. There will be plenty of legacy codebases written in these prophetically dead programming languages, and a need for developers with the know-how to understand and maintain them. Just look at legacy languages like COBOL, which still sits at the heart of countless enterprise software systems (including Fortune 500 companies).

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Perl was conceived in the 1980s as a scripting language designed for Unix system administration tasks, and subsequently gained popularity as a general-purpose programming language. Despite its age, the language hovers in 19th place on the TIOBE index, as it remains important in areas like data science and analytics. However, Perl commands much less mindshare now than it did a decade ago.

The release of Raku in 2019 -- a Perl spinoff designed by the language's creator, Larry Wall -- profoundly undercut community enthusiasm for Perl. Plans for future version releases counter the argument that Perl is already a dead programming language, but it is quickly turning into one that may find itself confined to legacy codebases.

11 Open Source DevOps Tools We Love For 2021

DevOps isn’t just a cultural shift — it requires great tools to come to fruition. Below, we’ve pulled together a list of some of the most well-loved DevOps tools available today. But, throwing loads of money into fancy SaaS solutions can quickly gobble up the cloud budget. These DevOps tools all are open source, and enable everything from container builds and orchestration to microservices networking, configuration management, CI/CD automation, full-stack monitoring and more. Here are some of our favorite open source DevOps tools for 2021.

Excellent Free Tutorials to Learn Haml - LinuxLinks

Haml (HTML Abstraction Markup Language) is a markup language that’s used to cleanly and simply describe the HTML of any web document, without the use of inline code.

Steinar H. Gunderson: plocate 1.1.6 released

I've released version 1.1.6 of plocate with some minor fixes; changelog follows.

Tools and Practices I Use In Every Real-World Software Project

There are very few books written for junior-to-mid level developers that answer the question “How do I run a real-world software project?”. Industry best practices often arise as the result of cross-pollination and institutional/tacit knowledge rather than explicitly prescribed rules that you can read about in a book.

For developers working alone or in small organizations such as startups, these norms may not be obvious. Knowing which tools one needs to deploy a production-scale application is crucial knowledge.

In 2019 I published the article “Software Tools for Hobby-Scale Projects.” It is still one of my most popular blog entries. This post will explore the same idea within a professional context and hopefully help new or solo developers get guidance on tools and practices for new projects at small to mid-scale organizations.

Objective: Provide a list of tools and practices that apply to a majority of real-world software projects.

Intended audience: Developers familiar with software authorship wishing to learn about real-world software deployments and practices.

The Sacred “Back” Button

Younger readers will find it hard to conceive of a time in which every application screen didn’t have a way to “Go Back”. This universal affordance was there, a new thing, in the first Web browser that anyone saw, and pretty soon after that, more or less everything had it. It’s a crucial part of the user experience and, unfortunately, a lot of popular software is doing it imperfectly. Let’s demand perfection.

Why it matters · Nobody anywhere is smart enough to build an application that won’t, in some situations, confuse its users. The Back option removes fear and makes people more willing to explore features, because they know they can always back out. It was one of the reasons why the nascent browsers were so much better than the Visual Basic, X11, and character-based interface dinosaurs that then stomped the earth.

Thus I was delighted, at the advent of Android, that the early phones had physical “back” buttons.

An easy to use MTP implementation for your next embedded Linux project

Did you know you could run a permissively-licensed MTP implementation with minimal dependencies on an embedded device? Here's a step-by-step guide on how to easily run cmtp-responder on a Rock Pi 4 or any other board equipped with a UDC.

To recap: In part1 of this series I introduced you to the concept of USB gadgets, their configfs composition interface, available opensource tools and basic systemd integration. In part2 I wrote about one particular USB gadget function - FunctionFS - and its integration with systemd. Then I presented cmtp-responder, a permisively-licensed MTP responder implementation and showed how to play with it on your PC with dummy_hcd driver. It is in this latter post that I promised you running cmtp-responder on real hardware. You can also watch me talking about USB gadgets at ELC 2019 and Linux Piter 2019.

Gradle Release Notes

This release enables file system watching by default to make your incremental builds faster, expands support for building projects with Java 16, and adds support for building on Macs using Apple Silicon processors (such as M1).

Gradle 7.0 released

The latest release of the Gradle build tool is now available. Gradle 7.0 enables file system watching by default to make incremental builds faster and expands support for building projects with Java 16 as well as Apple Silicon support.

When the file system is enabled in the new version, Gradle keeps what it learned from the file system in memory and skips reading from the file system on each build, reducing the amount of disk I/O needed to determine what has changed, the team explained.

The release also introduces a feature preview for centralized dependency versions and it enables build validation errors to make builds more reliable.

Claudio Cambra: On finishing Season of KDE: improving Kirigami docs

I wrote my first Season of KDE blog-post 3 months ago… and have since forgotten to write any updates. It’s time to address that!

Since January, I’ve been working mainly on improving the documentation for Kirigami. Back then, the Develop wiki had some pages teaching newcomers how to create a Kirigami application, but these were a little disjointed and didn’t really lead readers towards any specific goal.

There were also a lot of aspects and components of Kirigami that weren’t properly documented. Some of the existing materials also needed revising in terms of style, structure, and clarity.

Getting Started With MicroPython on the Raspberry Pi Pico

The Raspberry Pi Pico is the first microcontroller-based development board from the Raspberry Pi Foundation. Instead of the Linux operating system found on other Raspberry Pi boards, the Pico must be attached to another computer to program it.

Microcontroller programming is a difficult subject to learn, but luckily the Raspberry Pi foundation has made it easy to get up and running with the Pico. Today you'll learn how to install all the tools needed to get started with the Raspberry Pi Pico.

These instructions focus on Windows, but Linux and Mac installation are very similar, just make sure to get the tools for your operating system instead.

Calculating EV battery charge pricing with Perl

Presently I have great interest in “EVs” Electric Vehicles but I haven’t seen any data on how much it would cost to charge an electric vehicle from 0 % to 100 % battery charge at home in NYC ( So I wrote a Perl script to do just that ) but before we dig in into it I explain a few things about Electric Vehicles.

Electric Vehicles will have a battery capacity that is represented by kilowatt-hour units or kWh for short.

An EV’s driving range is represented in miles units ( In the US ) and the average mileage is determined by the EPA battery range rating ( the bigger the battery capacity usually means the more driving range you will have in a car ) after conducting a few tests ( so in reality your mileage will vary ).

Electric vehicles have an onboard charger which determines its charging rate in Kilowatt per Hour and it varies by car makers. Most EV car owners will install a Level 2 charger that is usually capable of charging cars up to 7.2 kWH rate using 220 volt electric circuit with 32 amps of power ( but there are chargers that can go at a higher rate ).

Ok now that I explained a few things lets dig into the data used to make my script.

I checked my electric bill and found that my electricity rate in NYC is $0.13 cents per kWh.

For comparison I phoned a friend in Florida to get electricity rates where he lives which is $ 0.07 cents per kWh. ( Almost half of NY rate )

How to Install and Use Ruby on Linux Distributions

Ruby is one of the most used and easy to use programming languages. Ruby is an open-source, object-oriented interpreter that can be installed on a Linux system. Many programmers prefer Python over Ruby to start learning basic programming, but Ruby can handle large web-frameworks and web applications. Once you start learning Ruby, you would find it less machine-like and not repetitive. If you’re confused between Ruby and Ruby on Rails, I must mention that they are not the same; Ruby is a programming language; on the other hand, Ruby on Rails is a web framework.

Open Source Software Leader the Eclipse Foundation Launches the Adoptium Working Group for Multi-Vendor Delivery of Java Runtimes for Enterprises

AWS's Shane Miller to head the newly created Rust Foundation

Miller, who leads the Rust Platform team for AWS, has been a software engineer for almost 30 years. At AWS, Miller has been a leader in open-source strategic initiatives and software engineering and delivery. Miller's Rust Platform team includes Rust language and compiler maintainers and contributors and developers on the Tokio runtime for writing reliable asynchronous applications with Rust. Under Miller's leadership, the AWS Rust team is crafting optimizations and tools for the features that engineers will use to build and operate services which take full advantage of Rust's performance and safety.

Inkscape compiled in OpenEmbedded

Cross-compiling can be a challenge with some packages, and some of the big ones, such as SeaMonkey, LibreOffice and Inkscape, I have compiled in a running EasyOS (with the "devx" SFS loaded).
I have previously compiled LibreOffice in OE, see the Pyro series. But it was a lot of work.

Felix Häcker: New Shortwave release

Ten months later, after 14.330 added and 8.634 deleted lines, Shortwave 2.0 is available! It sports new features, and comes with the well known improvements, and bugfixes as always.

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Shortwave has always been designed to handle any screen size from the beginning. In version 2.0 we have been able to improve this even further. There is now a compact mini player for desktop screens. This still offers access to the most important functions in a tiny window.

5 signs you're a groff programmer

I first discovered Unix systems in the early 1990s, when I was an undergraduate at university. I liked it so much that I replaced the MS-DOS system on my home computer with the Linux operating system.

One thing that Linux didn't have in the early to mid-1990s was a word processor. A standard office application on other desktop operating systems, a word processor lets you edit text easily. I often used a word processor on DOS to write my papers for class. I wouldn't find a Linux-native word processor until the late 1990s. Until then, word processing was one of the rare reasons I maintained dual-boot on my first computer, so I could occasionally boot back into DOS to write papers.

Then I discovered that Linux provided kind of a word processor. GNU troff, better known as groff, is a modern implementation of a classic text processing system called troff, short for "typesetter roff," which is an improved version of the nroff system. And nroff was meant to be a new implementation of the original roff (which stood for "run off," as in to "run off" a document).