OS/2 Archive

It’s been two years since the release of ArcaOS 5.1, which was a hugely important release because it brought UEFI support to this continuation of IBM’s OS/2, ensuring longevity for the project for years to come. Since I don’t think much is known about what, exactly, Arca Noae, and eComStation before it, has access to within the licensing agreement with IBM, it’s difficult to ascertain just how much room they actually have to make changes to the code at the core of the old OS/2. Regardless, I tested ArcaOS 5.1 before and during its release, and the support for UEFI and GPT partition layouts was excellent on my machines. Almost 18 months later comes the next release in the 5.1 branch, ArcaOS 5.1.1, and as the version number implies, this isn’t another major release on the scale of 5.1. Looking at the list of changes, it mostly contains a ton of upgraded versions of various programs and tools included in ArcaOS. After some digging into some of those upgraded versions, I think I can safely say we’re looking at a ton of small bugfixes, but there are also a few other things that stand out to me as welcome changes. For instance, the changelog mentions various improvements to the installer and related tools, such as an improved method of determining the right screen resolution and font scaling during the installation. Considering I had to deal with some issues there – I think the installer UI elements were grossly oversized – this is a welcome fix. There are also “refreshed” Firefox and Thunderbird builds, although I don’t know if that means an update to the latest ESR releases, or just a rebuild of what was already shipping with ArcaOS 5.1. I never found the time around the 5.1 release to do a proper review – I was knee-deep in baby and toddler care overload at the time – but if Arca Noae is willing to provide me with a 5.1.1 copy, I should be able to actually review it now that I’m only ankle-deep in baby and toddler care overload.

Most of us are aware that IBM’s OS/2 has excellent compatibility with DOS and Windows 3.x programs, to the point where OS/2 just ships with an entire installation of Windows 3.x built-in that you can run multiple instances of. In fact, to this day, ArcaOS, the current incarnation of the maintained and slightly modernised OS/2 codebase, still comes with an entire copy of Windows 3.x, making ArcaOS one of the very best ways to run DOS and Windows 3.x programs on a modern machine, without resorting to VMware or VirtualBox. Peter Hofmann took a look at one of the earlier versions of OS/2 – version 2.1 from 1993 – to see how its DOS compatibility actually works, or more specifically, the feature “DOS from drive A:”. You can insert a bootable DOS floppy and then run that DOS in a new window. Since this is called “DOS from drive A:”, surely this is something DOS-specific, right? Maybe only supports MS-DOS or even only PC DOS? Far from it, apparently. ↫ Peter Hofmann Hofmann wrote a little test program using nothing but BIOS system calls, meaning it doesn’t use any DOS system calls. This “real mode BIOS program” can run from the bootsector, if you wanted to, so after combining his test program with a floppy disk boot record, you end up with a bootable floppy that runs the test program, for instance in QEMU. After a bit of work, the test program on the bootable floppy will work just fine using OS/2’s “DOS from drive A:” feature, even though it shouldn’t. What this seems to imply is that this functionality in OS/2 2.1 looks a lot like a hypervisor, or as Hofmann puts it, “basically a builtin QEMU that anybody with a 386 could use”. That’s pretty advanced for the time, and raises a whole bunch of questions about just how much you can do with this.

This release marks the last time that Microsoft would release an OS/2 beta to developers, instead with the runaway success of Windows 3.0, Microsoft would remove resources from the constrained OS/2, and refocus both on Windows 3.1, and Windows NT. Thanks to one of my Patrons – Brian Ledbetter, the much-sought Microsoft OS/2 2.0 Pre-Release 2 is now available! So obviously the first thing to do was to re-create the original magical screenshot. ↫ neozeed at VirtuallyFun We already talked about this rediscovered release, but this article contains even more detailed information, this time from the person who bought the copy off eBay.

Just before the end of 1989, Microsoft made available the first pre-release version of the long promised 32-bit OS/2 2.0, which was intended to be the first mass-market 32-bit PC operating system. This was accompanied by a press release detailing the $2,600 OS/2 2.0 Software Development Kit (SDK). Unfortunately, the December 1989 pre-release of OS/2 2.0 may not have survived to the present day. But in June 1990, Microsoft shipped the second pre-release of the OS/2 2.0 SDK. And that version has now turned up, after twenty years of searching, and nearly a quarter century after its release! ↫ Michal Necasek at OS/2 Museum OS/2 is one of the biggest what-ifs in tech, and the whole origin story and demise of the platform is worthy of a big budget drama series. It also happens to be one of my favourite retrocomputing platforms of all time, so I may be biased.

Speaking of POWER – well, PowerPC – what about OS/2 Warp for PowerPC? What was OS/2 Warp, PowerPC Edition like? An unfinished product, rough around the edges but simultaneously technically very interesting and advanced and showing promise. Even though the OS/2 PPC release wasn’t called beta, it is obvious that this is a beta level product (if even that in some respects). Many features are unfinished or completely missing (networking in the first place). The kernel level code doesn’t look much like production build and prints out quite a lot of debugging output on the serial console. The HPFS support was very unstable, and the stability of Win-OS/2 left a lot to be desired. There were too many clearly unfinished parts of the product (documentation, missing utilities etc.). On the other hand a large portion of the system worked well. The user interface and graphics subsystem in general didn’t exhibit any anomalies. Multitasking was reliable and all things considered, responsiveness quite good for a 100MHz CPU and code that was not likely to have been performance tuned. The multimedia subsystem worked much better than I expected. Many things were much improved compared to Intel OS/2 — internationalization, graphics subsystem, updated console API and so on. The system seemed to have enough raw power, even if it wasn’t harnessed too well. Boot time was rather long but once up and running, the system was snappy (with some exceptions, notably the CD-ROM driver). To reach true production quality, the OS would have needed at least additional six months of intense development, probably more. I’m a tad bit jealous some people manage to find the right hardware to run OS/2 for PowerPC, since it’s incredibly high on my list. At least I have this great article to read through every now and then, until the day I manage to get lucky myself.

The spread of Mastodon clients to alternative platforms is continuing, and today, it’s OS/2’s – the one that got away – time in the spotlight. Robert Roland is working on a Mastodon client targeting OS/2, eComStation, and ArcaOS, but it’s all still early in development. The first bits of code were only uploaded yesterday, so there’s a long way yet to go – but if you want to follow along, you can go to Roland’s Mastodon account, and of course, if you want to help out, I’m sure he’d be delighted. I love OS/2 – in the form of the modern ArcaOS – and a working Mastodon client is something that’s quite high on my wish list. Who knows – maybe one of you nerds can help out with this project.

A few weeks ago I embarked on a somewhat crazy side project: Make the Open Watcom debugger work on OS/2 1.0. This project was not entirely successful, but I learned a couple of things along the way. I love these stories.

ArcaOS 5.0.8 includes refreshed driver content, updated kernel and included software, as well as installation boot fixes since 5.0.7 was released at the end of 2021. It also rolls in a few fixes that come from our 5.1.0 development work. ArcaOS 5.0.8 can be used for new installs or to update any prior version of ArcaOS 5. If you have experienced difficulty installing previous releases of ArcaOS on your hardware, 5.0.8 may address your issue(s). This is a small point release in the run-up to the release of ArcaOS 5.1.0, which will be a much bigger update, but that is currently held back by the developers having to redesign their ISO delivery stack. The wiki has all the detailed changes since 5.0.7.

In the mid-1980’s, Microsoft produced an expansion card for the IBM PC and PC XT, known as the Mach 10. In addition to occupying an expansion slot, it also replaced your CPU: You unplugged your old and busted 4.77 MHz 8088 CPU and plugged into the now-empty socket a special adapter that led via a ribbon cable back to the Mach 10 card. On the Mach 10 card was the new hotness: A 9.54 MHz 8086 CPU. This gave you a 2× performance upgrade for a lot less money than an IBM PC AT. The Mach 10 also came with a mouse port, so you could add a mouse without having to burn an additional expansion slot. The Mach 20 took the same basic idea as the Mach 10, but to the next level: As before, you unplugged your old 4.77 MHz 8088 CPU and replaced it with an adapter that led via ribbon cable to the Mach 20 card, which you plugged into an expansion slot. This time, the Mach 20 had an 8 MHz 80286 CPU, so you were really cooking with gas now. And, like the Mach 10, it had a mouse port built in. According to a review in Info World, it retailed for $495. Microsoft also produced a customized version of OS/2 for the Mach 20. Despite being tailor-made for the Mach 20, it still had terrible performance problems. One of my former colleagues spoke with the person who took over from him as the support specialist for OS/2 for Mach 20. According to that person’s memory (which given the amount time that has elapsed, means that we should basically be saying “according to legend” at this point), a total of eleven copies of “OS/2 for Mach 20” were ever sold, and eight of them were returned. That leaves three customers who purchased a copy and didn’t return it. And the support specialist had personally spoken with two of them. If these numbers are accurate, I believe this makes OS/2 for Mach 20 a strong candidate for being the worst-selling actually-shipped Microsoft software product of all time. We have to find this. Someone must have a copy of OS/2 for Mach 20 in a box in the attic somewhere. This is the final boss of software preservation.

Slovenia being a tiny country with a population of just 2 million, IBM OS/2 Warp 4 was one of the few non-Microsoft operating systems to be localized to Slovenian in the mid-90s and a big deal for the local IT community back then. But nearly 3 decades later, when OS/2 disappeared from the last ATMs in the country, the even rarer Slovenian version was as good as completely gone. Or was it? This is an amazing example of digital archeology, and I hope the other rare OS/2 translations are found as well. It’s difficult for small – but stunningly beautiful! – countries to maintain their digital independence, and properly localised software plays a huge role in that.

ArcaOS 5.0.7 includes refreshed driver content, updated kernel and included software, as well as installation boot fixes since 5.0.6 was released in 2020. If you have experienced difficulty installing previous releases of ArcaOS on your hardware, 5.0.7 may address your issue(s). If installing from USB stick, the image may be created using any major operating system at hand (Windows, Linux, MacOS, and of course, OS/2, eComStation, and ArcaOS). Once built, the USB stick can be inserted into any USB port in the target system to boot into the ArcaOS installer/updater. This is an important update, as boot issues during installation were a problem on all my machines. I’m hoping this release will address them, since running ArcaOS on real hardware, instead of in a virtual machine, makes me giddy with excitement – especially since an updated, modern browser is on its way, too.

Arca Noae’s approach to supporting GPT will be multi-phased, with the first phase of development currently underway and anticipated for release with ArcaOS 5.1. The design specification of our initial GPT support is to allow for partitions up to the current 2TB maximum size, with multiple partitions of this size possible on disks larger than 2TB. Our specification further provides that ArcaOS be able to create, delete, and modify GPT partitions which are identified by their GUIDs as being “OS/2-type” partitions, and lastly, that GPT support be available for both traditional BIOS (for data volumes) and UEFI-based systems (for boot and data volumes). This is one of the biggest hurdles for ArcaOS to overcome, and I’m glad they’ve committed to tackling it. Having to partition an entire disk in legacy MBR just to be able to run ArcaOS on real hardware is a major barrier to entry.

ArcaOS 5.0.6 includes refreshed content and fixes since 5.0.5 was released. If you have experienced difficulty installing previous releases of ArcaOS on your hardware, 5.0.6 may address your issue(s). If installing from USB stick, the image may be created using any major operating system at hand (Windows, Linux, MacOS, and of course, OS/2, eComStation, and ArcaOS). Once built, the USB stick can be inserted into any USB port in the target system to boot into the ArcaOS installer/updater. It’s a relatively minor release, but anything that improves the chances of being able to install ArcaOS I’ll take. I’ve had some major issues getting it to boot on modern hardware – despite excellent help from the ArcaOS team, we couldn’t get it to work – so I hope I can find some time somewhere to try it again.

ArcaOS 5.0.5 introduces support for xHCI (USB3) controllers to install on a wider array of systems than ever before. What’s more, for updaters, even if your USB controller was previously unsupported, and you had to install or update from DVD in the past, you may now boot into the installer from USB stick to perform the update. USB3-attached keyboards and mice should work, as well. ArcaOS 5.0.5 includes over 100 updates, enhancements, and fixes since 5.0.4 was released. If you have experienced difficulty installing previous releases of ArcaOS on your hardware, the fixes and updates included in 5.0.5 may address your issue(s). ArcaOS is a continuation of IBM’s OS/2, updated and fixed for modern hardware and with modern applications.