Author Archives: Michal Necasek

Missing XENIX Disks

Posted on July 22, 2024 by Michal Necasek

The previously mentioned warez mega dump contains disk images of SCO 286 XENIX 2.1.0. The release appears to be from February 1986. It is the oldest SCO 286 XENIX release that I know of. But there’s a hitch. The warez … Continue reading →

Posted in 286, Archiving, SCO, Xenix | 17 Comments

1989 Networking: NetWare 386

Posted on July 20, 2024 by Michal Necasek

Thanks to the recent warez mega dump, another long lost gem has come to light: NetWare 386, also known as NetWare 3.0. In September 1989, Novell released NetWare 386 V3.0, the first in a long line of 32-bit network operating … Continue reading →

Posted in 386, NetWare, Networking, Novell, PC history | 22 Comments

More MS OS/2 2.0

Posted on June 30, 2024 by Michal Necasek

Over the last few weeks, two “new” pre-releases of OS/2 2.0 have been found in ancient warez archives. The first is OS/2 2.0 build 6.64, released in early April 1990: In general, this build is not substantially different from the … Continue reading →

Posted in IBM, Microsoft, OS/2, Pre-release | 5 Comments

Who Knew What When

Posted on June 28, 2024 by Michal Necasek

When Microsoft released the unique early beta build of Multitasking DOS 4, I quickly found out that it does not run in VirtualBox: This was a bit of a surprise, because the more-or-less released versions of Multitasking DOS 4 from … Continue reading →

Posted in 286, DOS, IBM, Microsoft, PC architecture, PC history, VirtualBox | 26 Comments

Learn Something Old Every Day, Part XII: Strange File Resizing on DOS

Posted on June 7, 2024 by Michal Necasek

Someone recently asked an interesting question: Why do Microsoft C and compatible DOS compilers have no truncate() and/or ftruncate() library functions? And how does one resize files on DOS? OK, that’s actually two questions. The first one is easy enough … Continue reading →

Posted in Computing History, CP/M, Development, Documentation, DOS, Microsoft | 27 Comments

Learn Something Old Every Day, Part XI: DOS Directory Searches are Bizarre

Posted on May 7, 2024 by Michal Necasek

A while ago I started playing with EMU2, a piece of software which calls itself “A simple text-mode x86 + DOS emulator”. It is indeed relatively simple, only emulating an 8086 (or maybe 80186, with little bits of 80286 here … Continue reading →

Posted in Development, DOS, Undocumented | 52 Comments

Learn Something Old Every Day, Part X: The VGA Attribute Controller Is Weird

Posted on May 3, 2024 by Michal Necasek

A few days ago I finally swatted a VGA emulation bug that I had known about for several years, but couldn’t identify until recently. The problem affected only Windows 3.1 running in Standard mode. It did not occur in Windows … Continue reading →

Posted in Bugs, PC hardware, VGA | 9 Comments

How Not To Release Historic Source Code

Posted on April 26, 2024 by Michal Necasek

This is how to not do it: GitHub Don’t get me wrong, it’s absolutely brilliant that Microsoft was able to release a fairly complete (minus DOSSHELL) source code for MS-DOS 4.00 or 4.01 (see below). As much as it was … Continue reading →

Posted in Development, DOS, Source code | 81 Comments

The Future That Never Was

Posted on March 4, 2024 by Michal Necasek

Microsoft OS/2 2.0 SDK Pre-Release 2, June 1990 In 1990, the strategic PC operating system of Microsoft and IBM was not DOS, not Windows, but OS/2. The first 16-bit OS/2 was initially released in 1987 with a reduced feature set, … Continue reading →

Posted in 386, IBM, LAN Manager, Microsoft, OS/2, PC history, Pre-release | 76 Comments

Unlocking NetWare 2.0a

Posted on February 23, 2024 by Michal Necasek

A few months ago, the OS/2 Museum obtained a seemingly complete and error-free set of floppies with SFT NetWare 286 Level II version 2.0a. And just recently, a disk set of Advanced NetWare 86 2.0a turned up, though sadly incomplete. … Continue reading →

Posted in NetWare, Software Hacks | 19 Comments