The PowerPC adventure—by far the most exotic release of OS/2| www.os2museum.com
I have recently explored (again) the possibility of writing a high-res display driver for virtualized OS/2. But I ran (again) into a dizzying array of possible solutions, each with its own advantages and a good deal of drawbacks.| www.os2museum.com
Large companies like IBM, Microsoft, or Novell typically had a well defined process for releasing software on floppies. More often than not, files were not directly copied onto a physical floppy; instead, a tool was used to create an image … Continue reading →| OS/2 Museum
I was recently made aware of something that I had noticed before, but never paid much attention to. Consider this screenshot of a BIOS POST screen: VGA text modes usually use 720×400 resolution and 8×16 fonts (expanded to 9×16). The … Continue reading →| OS/2 Museum
Investigating the rather odd behavior of the Microsoft OS/2 1.21 disk driver led me to Compaq and their EXTDISK.SYS driver. While experimenting with various setups, I realized that DOS versions older than 5.0 do not support more than two hard … Continue reading →| OS/2 Museum
I just spent an inordinate amount of time debugging a VM running OS/2 Warp Server Advanced SMP (WSA SMP). The VM was working fine (except for sometimes hanging very early during boot, a known issue with the SMP kernel), but … Continue reading →| OS/2 Museum
In 1990, Microsoft released LAN Manager (LM) 2.0, a member of a long line of Microsoft’s networking products that started with MS-NET circa 1984 and eventually morphed into Windows NT file sharing. LAN Manager 1.0 was released in 1988 as … Continue reading →| OS/2 Museum
A while ago I discovered an antique pirated copy of IBM DOS 4.00 on 5.25″ media, which was something that was missing in my archive. And by antique I mean from August 1988, when DOS 4.0 was practically brand new. … Continue reading →| OS/2 Museum
An earlier article explored the history of codepage 852 (Latin-2 PC codepage) in released and pre-release versions of DOS and OS/2. At the time of this writing (June 2025), the earliest OS/2 build with some form of CP852 support including … Continue reading →| OS/2 Museum
Recently I had an opportunity to reacquaint myself with the DOS KEYB utility. KEYB is interesting in that it is designed primarily for international users, but one can also run KEYB US to load KEYB with standard US layout. It … Continue reading →| OS/2 Museum
The previously mentioned warez dump on archive.org contains a lot of little gems that would have been otherwise lost. One of those might be 3Com’s networking package from 1989, the 3+Open LAN Manager version 1.1. The software was released in … Continue reading →| OS/2 Museum
The other day I wanted to look up a specific IBM PS/2 model, a circa 1992 PS/2 Server system. So I punched the model into Google, and got this: That did not look quite right, since the machine I was … Continue reading →| OS/2 Museum
This is a follow-up to a previous post about the curious driver in Microsoft OS/2 1.21. After initially writing the article, additional information came to light, explaining why the code was there. In summer 1988, Compaq released the Deskpro 386/25, … Continue reading →| OS/2 Museum
Attempting to install Microsoft OS/2 1.21 will fail on many systems with the following scary looking error: Pressing Enter as directed shows the following more detailed error message: The initial boot phase, as well as the installation stage immediately before … Continue reading →| OS/2 Museum
At long last, I got hold of a decently well functioning ESDI drive. From my earlier adventures, I had a WD1007V-SE2 controller, as well as an older WD1007A. The WD1007A (Compaq branded) used to live in a Hyundai 286 machine … Continue reading →| OS/2 Museum
Last Friday I had a moment of panic. While investigating why different run-time libraries might interpret file timestamps differently, I noticed that even Windows doesn’t always agree with itself. When was dos4gw.exe last modified, at 10:14 PM or 9:14 PM? … Continue reading →| OS/2 Museum
Last week I amused myself by porting some source code from Watcom C to Microsoft C. In general that is not difficult, because Watcom C was intended to achieve a high degree of compatibility with Microsoft’s C dialect. Yet one … Continue reading →| OS/2 Museum
The other day I spent a while trying to understand the purpose of a rather strange looking piece of code inside Borland’s THELP.COM utility shipped with Turbo Pascal 6.0 (THELP.COM was misbehaving under emulated DOS). The THELP utility performs the … Continue reading →| OS/2 Museum
So here I am, writing a bit of test code to figure out the behavior of x87 FPUs with regard to saving and loading the FPU state (FSTENV/FLDENV and FSAVE/FRSTOR instructions in different modes and formats). The original real-mode only … Continue reading →| OS/2 Museum
A previous blog post explored the semi-mysterious yet sometimes highly useful DOS APPEND command. Now it’s time to look at its relatives: ASSIGN, JOIN, and SUBST. ASSIGN ASSIGN is the oldest of the bunch. It was written by IBM and … Continue reading →| OS/2 Museum
So I was working on improving a DOS emulator, when I found that something seemingly trivial wasn’t working right when COMMAND.COM was asked to do the following: echo AB> foo.txtecho CD>> foo.txt Instead of ABCD, foo.txt contained ABBC. I verified … Continue reading →| OS/2 Museum
For a long time, I couldn’t quite grasp what the DOS APPEND command could possibly be good for. Until I came across a situation which APPEND was made for.| www.os2museum.com
Solaris 2.1 for x86, also known as SunOS 5.1, was Sun’s first entry into the PC market (technically it was SunSoft, a subsidiary of Sun Microsystems, who released Solaris). However, it wasn’t Sun’s first x86 operating system. In the late 1980s, Sun sold 386i workstations based on Intel 386 processors. The 386i workstations were not PC compatible and ran SunOS 4.0, a BSD UNIX derivative with many custom Sun enhancements.| www.os2museum.com
This is how to not do it:| www.os2museum.com