Slack, Now On Windows 3.1

December 23, 2019 by Zoe Skyforest 20 Comments

Slack is either an online collaboration tool, or a religion, depending on who you talk to. Naturally, it’s accessible across all manner of modern platforms, from Windows and MacOS to smartphones. However, some prefer to go further back. At a recent company hackathon, [Yeo Kheng Meng] decided to create a Slack client for Windows 3.1.

This is how you learned to program before the Internet.

Programming for an older OS, in this case, Windows For Workgroups 3.11, requires setting up a viable development environment. Visual C++ 1.52 was pressed into service in this case, being the last version capable of targeting Windows 3.11. The development environment is run on a Windows 2000 virtual machine running on a Mac laptop. This was chosen for its ability to run 16-bit apps, and its Samba compatibility with both Windows 3.11 and Windows 10 and modern Macs.

There were several challenges to face along the way. Old school Windows simply isn’t capable of dealing with HTTPS, necessitating a proxy to handle the exchange of packets with Slack servers. Additionally, memory management was a hassle due to the limits of the 16-bit architecture. Thankfully, an old programming manual from the era was of great help in this regard.

At the end of the hackathon, a usable Slack client was up and running, complete with garish colors from the early Windows era. There’s a few key features missing, such as the ability to resolve user IDs, but overall, the concept works. We’ve seen [Yeo]’s work with this vintage OS before too. Video after the break.

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Catch The Old School BASIC Bug With This Computer Kit

December 12, 2019 by Tom Nardi 27 Comments

Does the complexity of modern computing ever get you down? Do you find yourself longing for the old days, where you could actually understand what your desktop machine’s hardware and software was doing at any given moment? You aren’t alone, but unfortunately running a 40+ year old computer as your daily driver isn’t really a viable option.

But that doesn’t mean you don’t have options. [Kostas] writes in to tell us about the “CB2 micro”: a diminutive open source retrocomputer kit that can be built in as little as 30 minutes thanks to its through-hole construction and exceptionally low parts count. When completed the miniature computer is an all-in-one BASIC development platform; just connect up a display and a PS/2 keyboard, and you’ve got everything you need to write you own programs or run games and applications developed by the community. You don’t even need a floppy, as the ATmega644P powered board has enough internal flash to store eight programs for easy access through its graphical menu system.

For many in the audience, a cheap little board that you can assemble yourself and use as a stand-alone BASIC experimentation platform is appealing enough. But thanks to a collection of hardware add-on boards, the CB2 micro can be augmented with some interesting capabilities.

Some are fairly obvious such as adding additional flash storage or RAM, but you can also run the computer on AA or AAA batteries, or add an S-Video port. [Kostas] even explains how to assemble a special serial cable that allows you to network multiple boards together. If you take the plunge and start building your own hardware modules, the sky’s the limit.

Of course, purists may balk because the CB2 micro isn’t using a “real” computer processor. Fair enough. For those that want a more authentic retro experience, you could always pick up a kit like the RC2014, or go all out and cram a Z80 into an Altoids tin so you can carry it around with you.

Patch, Or Your Solid State Drives Roll Over And Die

December 10, 2019 by Jenny List 117 Comments

Expiration dates for computer drives? That’s what a line of HP solid-state drives are facing as the variable for their uptime counter is running out. When it does, the drive “expires” and, well, no more data storage for you!

There are a series of stages in the evolution of a software developer as they master their art, and one of those stages comes in understanding that while they may have a handle on the abstracted world presented by their development environment they perhaps haven’t considered the moments in which the real computer that lives behind it intrudes. Think of the first time you saw an SQL injection attack on a website, for example, or the moment you realised that a variable type is linked to the physical constraints of the number of memory locations it has reserved for it. So people who write software surround themselves with an armoury of things they watch out for as they code, and thus endeavour to produce software less likely to break. Firmly in that arena is the size of the variables you use and what will happen when that limit is reached.

Your Drive Is Good For About 3 Years And 9 Months

Sometimes though even developers that should know better get it wrong, and this week has brought an unfortunate example for the enterprise wing of the hardware giant HP. Their manufacturer has notified them that certain models of solid-state disk drives supplied in enterprise storage systems contain an unfortunate bug, in which they stop working after 32,768 hours of uptime. That’s a familiar number to anyone working with base-2 numbers and hints at a 16-bit signed integer in use to log the hours of uptime. When it rolls over the value will then be negative and, rather than the drive believing itself to be in a renewed flush of youth, it will instead stop working.

Egg on the faces of the storage company then, and an urgently-released patch. We suspect that if you own a stack of these drives you will already know about the issue and be nervously pacing the racks of your data centre.

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Behind Amazon’s Doors Is A Library

December 6, 2019 by Al Williams 7 Comments

Some people love Amazon, while others think it has become too big and invasive. But you have to admit, they build gigantic and apparently reliable systems. Interestingly, they recently released a library of white papers from their senior staff called the Builder’s Library.

According to their blog post:

The Amazon Builders’ Library is a collection of living articles that take readers under the hood of how Amazon architects, releases, and operates the software underpinning Amazon.com and AWS. The Builders’ Library articles are written by Amazon’s senior technical leaders and engineers, covering topics across architecture, software delivery, and operations. For example, readers can see how Amazon automates software delivery to achieve over 150 million deployments a year or how Amazon’s engineers implement principles such as shuffle sharding to build resilient systems that are highly available and fault tolerant.

The Amazon Builders’ Library will continue to be updated with new content going forward.

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Audio Processing In Rust

November 14, 2019 by Al Williams 4 Comments

[Michael] volunteers with emergency services, and sometimes has to monitor radio traffic. Sometimes there’s a lot to review, and to make it easier he wrote a noise gate — think of it as a squelch — to break apart recorded audio into parts. Rust has been gaining popularity for writing low level software, and that’s the language he uses. However, you’ll see even if you don’t know Rust, it is pretty easy to figure out.

For test data, [Michael] took some publicly-available recordings of air traffic control. Using some ready-made audio processing functions and a simple state machine makes the code easy to write.

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Unix Tell All Book From Kernighan Hits The Shelves

October 29, 2019 by Al Williams 56 Comments

When you think of the Unix and C revolution that grew out of Bell Labs, there are a few famous names. Dennis Ritchie, Ken Thompson, and Brian Kernighan come to mind. After all, the K in both K&R C and in AWK stand for Kernighan. While Kernighan is no stranger to book authorship — he’s written several classics including “the white book” for C and Unix — he has a new book out that is part historical record and part memoir about the birth of Unix.

Usually, when a famous person writes a retrospective like this, it is full of salacious details, but we don’t expect much of that here. The book talks about Bell Labs and Multics, of course. There’s serious coverage of the first, sixth, and seventh editions with biographies of people integral to those releases.

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File Compression By Steganography

October 19, 2019 by Sharon Lin 29 Comments

In a world with finite storage and an infinite need for more storage space, data compression becomes a very necessary problem. Several algorithms for data compression may be more familiar – Huffman coding, LZW compression – and some a bit more arcane.

[Labunsky] decided to put to use his knowledge of steganography to create a wholly unique form of file compression, perhaps one that may gain greater notoriety among other information theorists.

Steganography refers to the method of concealing messages or files within another file, coming from the Greek words steganos for “covered or concealed” and graphe for “writing”. The practice has been around for ages, from writing in invisible ink to storing messages in moon cakes. The methods used range from hiding messages in images to evade censorship to hiding viruses in files to cause mayhem.

The developer explains that since every file is just a bit sequence, observing files leads to the realization that a majority of bits will be equal on the same places. Rather than storing all of the bits of a file, making modifications to the hard drive at certain locations can save storage space. What is important to avoid, however, is lossy file compression that can wreak havoc on quality during the compression stage.

The compression technique they ended up implementing is based on the F5 algorithm that embeds binary data into JPEG files to reduce total space in the memory. The compression uses libjpeg for JPEG decoding and encoding, pcre for POSIX regular expressions support, and tinydir for platform-independent filesystem traversal. One of the major modifications was to save computation resources by disabling a password-based permutative straddling that uniformly spreads data among multiple files.

One caveat – changing even one bit of the compressed file could lead to total corruption of all of the data stored, so use with caution!