General Development Archive

Programming time, dates, timezones, recurring events, leap seconds... Everything is pretty terrible.

The common refrain in the industry is Just use UTC! Just use UTC! And that's correct... Sort of. But if you're stuck building software that deals with time, there's so much more to consider.

It's time... To talk about time.

In the wake of the recent Meltdown and Spectre vulnerabilities, it's worth spending some time looking at root causes. Both of these vulnerabilities involved processors speculatively executing instructions past some kind of access check and allowing the attacker to observe the results via a side channel. The features that led to these vulnerabilities, along with several others, were added to let C programmers continue to believe they were programming in a low-level language, when this hasn't been the case for decades.

Processor vendors are not alone in this. Those of us working on C/C++ compilers have also participated.

This doesn’t have to be forever. Maybe in the future, developers will start using React Native to build desktop applications. Or perhaps Flutter! Electron apps have a bad reputation for using too much RAM, have potential security issues, can’t (yet) match the speed of C++, and they often lack the polish and familiarity of a great native app.

But it seems clear to me that OS-specific SDKs are becoming a liability for desktop OS vendors. Developers want to use the technologies they know, and they want maximum reach for the products they build. And they’re smart enough to get what they want. A lack of cooperation on the part of Apple, Google, and Microsoft will only hurt users.

Say hello to your new Electron overlord.

By far, the worst part of working on beets is dealing with filenames. And since our job is to keep track of your files in the database, we have to deal with them all the time. This post describes the filename problems we discovered in the project's early days, how we address them now, and some alternatives for the future.

Honestly, I don't think the Atari 2600 BASIC has ever had a fair review. It's pretty much reviled as a horrible program, a horrible programming environment and practically useless. But I think that's selling it short. Yes, it's bad (and I'll get to that in a bit), but in using it for the past few days, there are some impressive features on a system where the RAM can't hold a full Tweet and half the CPU time is spent Racing The Beam. I'll get the bad out of the way first.

Input comes from the Atari Keypads, dual 12-button keypads. If that weren't bad enough, I'm using my keyboard as an emulated pair of Atari Keypads, where I have to keep this image open at all times.

Okay, here's how this works.

• Direct3D 10 and 11 support.
• The Direct3D command stream.
• The Android graphics driver.
• Improved DirectWrite and Direct2D support.

Swift 4 is now officially released! Swift 4 builds on the strengths of Swift 3, delivering greater robustness and stability, providing source code compatibility with Swift 3, making improvements to the standard library, and adding features like archival and serialization.

You can watch a quick overview of it by watching the WWDC 2017: What's New in Swift presentation, and try out some of the new features in this playground put together by Ole Begemann.

Later this year, on November 21, 2017, D-Bus will see its 15th birthday. An impressive age, only shy of the KDE and GNOME projects, whose collaboration inspired the creation of this independent IPC system. While still relied upon by the most recent KDE and GNOME releases, D-Bus is not free of criticism. Despite its age and mighty advocates, it never gained traction outside of its origins. On the contrary, it has long been criticized as bloated, over-engineered, and orphaned. Though, when looking into those claims, you’re often left with unsubstantiated ranting about the environment D-Bus is used in. If you rather want a glimpse into the deeper issues, the best place to look is the D-Bus bug-tracker, including the assessments of the D-Bus developers themselves. The bugs range from uncontrolled memory usage, over silent dropping of messages, to dead-locks by design, unsolved for up to 7 years. Looking closer, most of them simply cannot be solved without breaking guarantees long given by dbus-daemon(1), the reference implementation. Hence, workarounds have been put in place to keep them under control.

Nevertheless, these issues still bugged us! Which is, why we rethought some of the fundamental concepts behind the shared Message Buses defined by the D-Bus Specification. We developed a new architecture that is designed particularly for the use-cases of modern D-Bus, and it allows us to solve several long standing issues with dbus-daemon(1). With this in mind, we set out to implement an alternative D-Bus Message Bus. Half a year later, we hereby announce the dbus-broker project!

Cooper Harasyn found a Super Mario World save corruption glitch, and we worked together to create a jailbreak that works on real, unmodified cartridges and Super Nintendos.

An SBX container is composed of a collections of blocks with size submultiple/equal to that of a sector, so they can survive any level of fragmentation. Each block has a minimal header that includes a unique file identifier, block sequence number, checksum, version. Additionally, non-critical info/metadata are contained in block 0 (like name, file size, crypto-hash, other attributes, etc.).

If disaster strikes, recovery can be performed simply by scanning a volume/image, reading sector-sized slices and checking block signatures and then CRCs to detect valid SBX blocks. Then the blocks can be grouped by UIDs, sorted by sequence number and reassembled to form the original SeqBox containers.

Modern computer science is dominated by men. But it hasn't always been this way.

A lot of computing pioneers - the people who programmed the first digital computers - were women. And for decades, the number of women studying computer science was growing faster than the number of men. But in 1984, something changed. The percentage of women in computer science flattened, and then plunged, even as the share of women in other technical and professional fields kept rising.

What happened?

This release is the result of the community's work over the past six months, including: use of profile data in ThinLTO, more aggressive dead code elimination, experimental support for coroutines, experimental AVR target, better GNU ld compatibility and significant performance improvements in LLD, as well as improved optimizations, many bug fixes and more.

In this article we'll walk through an example of how to interpret a closed source program, how to analyze its behavior, and how to ultimately alter that behavior to do what we want. These techniques are well known within many circles, but few tutorials exist to help people get started. The context for this example investigation is the linker's subsystem field generation, but the techniques can be applied to other problems that seem interesting.