Category Archives: DOS

MS-DOS 1.1, 2.0 Source Code Released

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 | 52 Comments

The Central Point Backup Floppy Format

A reader recently asked about the “native” format of Central Point Backup (CP Backup) floppies. Diskettes formatted in this manner are somewhat tricky to work with as they do not use a standard DOS format. A session with Sydex’s AnaDisk … Continue reading

Posted in DOS, Floppies | 27 Comments

Kids these days…

By sheer accident I stumbled on this document. In summary, it’s about a bunch of school kids working on a computer history preservation project and trying to archive a big box of floppies from George Alistair Sanger, a video game … Continue reading

Posted in DOS, Floppies | 22 Comments

PC DOS Retro

There’s a new DOS history and reference information website called simply “PC DOS Retro Page”. The site includes several reference pages (DOS commands, drivers, functions, internal structures) as well as a very extensive timeline of DOS releases. Vernon Brooks, the … Continue reading

Posted in DOS | 16 Comments

DOS Goodies at

The excellent last week uploaded scans of several IBM Personal Computer DOS manuals. Included are the manuals for DOS 1.0 (1982), 1.1, and 2.0, a preliminary technical reference for DOS 3.1, the DOS 3.1 user’s reference manual, and DOS … Continue reading

Posted in DOS, IBM | 1 Comment

The Oldest OS/2 Executable In the Wild

While researching the history of Microsoft’s segmented-executable linker originally called LINK4.EXE, I came across an OS/2 executable that was publicly released almost a year before the first OS/2 SDK was shipped, and many months before OS/2 was even announced. In … Continue reading

Posted in DOS, Microsoft, OS/2 | 4 Comments

Fixing Broken LINK4

The recently-mentioned multitasking DOS 4 disk images came with a linker called LINK4.EXE. The ‘4’ in fact stands for ‘DOS 4’, although most people who used LINK4 never saw multitasking DOS 4 (LINK4 was shipped with 16-bit Windows SDKs). LINK4 was … Continue reading

Posted in DOS, Microsoft | 5 Comments

Multitasking MS-DOS 4.0 Lives

Something rather unexpected happened over the weekend: disk images of the near-mythical multitasking DOS 4 suddenly popped up. This is “MS-DOS Version 4.00”—from 1985. It looks almost exactly like MS-DOS 3.0, with COMMAND.COM, FORMAT, SYS, FDISK, JOIN, SUBST, ATTRIB, and … Continue reading

Posted in DOS, Microsoft | 36 Comments

Book Review: DOS Internals

A Few Decades Late Book Reviews DOS Internals, by Geoff Chappell Addison-Wesley, March 1994; 768 pages, ISBN 0-201-60835-9; $39.95 DOS Internals is a very unusual book. Written by an academic whose field isn’t computer science, it is a in-depth and … Continue reading

Posted in Books, Development, DOS, Microsoft | 6 Comments

Book Review: Developing Applications Using DOS

A Few Decades Late Book Reviews Developing Applications Using DOS, by Ken W. Christopher, Jr., Barry A. Feigenbaum, and Shon O. Saliga John Wiley & Sons, February 1990; 573 pages, ISBN 0-471-52231-7; $24.95 Developing Applications Using DOS is a surprisingly obscure … Continue reading

Posted in Books, DOS, IBM | 1 Comment