Category Archives: Microsoft

Semantic Differences, Microsoft v. Microsoft

Posted on August 8, 2014 by Michal Necasek

While comparing the behavior of various versions of old Microsoft C compilers, I tried building a trivial hello-world type program with CL.EXE from Microsoft C/C++ 7.0 (March 1992) running on top of a 32-bit Windows Server 2003. This seemingly trivial … Continue reading →

Posted in DOS, Microsoft, Virtualization | 14 Comments

Windows Presentation Manager Documentation

Posted on July 20, 2014 by Michal Necasek

The OS/2 Museum just posted a three-volume set of draft Windows Presentation Manager reference documentation. This refers to the OS/2 Presentation Manager GUI but highlights the story Microsoft pushed in 1987: Windows and OS/2 both used the same graphical user … Continue reading →

Posted in Documentation, Microsoft, OS/2 | 5 Comments

OS/2 Programmer’s Toolkit

Posted on July 11, 2014 by Michal Necasek

For those wishing to write OS/2 1.x programs, the complete Microsoft OS/2 Programmer’s Toolkit documentation is now online. This is Microsoft’s programming documentation for OS/2 1.0 programming. It is worth noting that IBM’s programming documentation was different; worse yet, IBM’s … Continue reading →

Posted in Development, Documentation, Microsoft, OS/2 | 2 Comments

Weekend Reading, OS/2 and Windows

Posted on July 4, 2014 by Michal Necasek

In a recent post I mentioned that the OS/2 Museum’s stack of PC Tech Journal issues ironically does not include the first PCTJ issue devoted to OS/2. Thanks to pcjs.org, the October 1987 issue of PCTJ can now be read … Continue reading →

Posted in Documentation, Microsoft, OS/2, Windows | 3 Comments

Careful with that Buffer…

Posted on June 29, 2014 by Michal Necasek

Last week I was sorting through several sets of Microsoft C 5.1 disks from 1988  (more about that later). While I was comparing the disk images to see whether the disks were the same or not, despite different labels and part … Continue reading →

Posted in Microsoft, Security | 13 Comments

Microsoft OS/2 1.3… But Which One?

Posted on May 7, 2014 by Michal Necasek

A recent inventory at the OS/2 Museum revealed that two seemingly identical sets of Microsoft OS/2 1.30.1 disk images were in fact not identical at all. Probably thanks to the twilight status of OS/2 at Microsoft in the days of OS/2 1.3, Microsoft … Continue reading →

Posted in LAN Manager, Microsoft, OS/2 | 26 Comments

OEM MS OS/2: 1987-1990

Posted on April 18, 2014 by Michal Necasek

When Microsoft started offering OS/2, the arrangement was roughly similar to how DOS 3.3 had been handled: Microsoft and IBM jointly developed the code, IBM maintained its own version, and Microsoft licensed an “adaptation kit” to OEMs. While the IBM … Continue reading →

Posted in Microsoft, OS/2 | 18 Comments

Multitasking MS-DOS 4.0, Goupil OEM

Posted on April 9, 2014 by Michal Necasek

The recently unearthed copy of the near-mythical Multitasking (aka European) MS-DOS 4.0 clearly did not want to be alone. James Lariviere, a kind reader of this blog, provided a disk image of multitasking DOS 4 which was released in 1986 … Continue reading →

Posted in DOS, Microsoft, OS/2 | 29 Comments

MS-DOS 1.1, 2.0 Source Code Released

Posted on March 25, 2014 by Michal Necasek

In cooperation with the excellent Computer History Museum in Mountain View, Microsoft released the source code to MS-DOS 1.1, MS-DOS 2.0, and Microsoft Word for Windows 1.1a. Here’s hoping that this is a sign of things to come and Microsoft … Continue reading →

Posted in DOS, Microsoft, PC history | 53 Comments

IBM OS/2 1.0 in a VM

Posted on March 21, 2014 by Michal Necasek

As previously mentioned, IBM’s OS/2 1.0 and 1.1 is extra unfriendly to modern hypervisors. To recap, there is a curious difference between IBM’s and Microsoft’s kernels in OS/2 1.0/1.1 with regard to mode switching. For reasons that aren’t very clear, … Continue reading →

Posted in IBM, Microsoft, OS/2, VirtualBox, Virtualization | 36 Comments