Category Archives: Development

Phantom 3.0

As previously mentioned, the OS/2 Museum adapted the Phantom redirector example from the second edition of Undocumented DOS to demonstrate that the redirector interface was already fully implemented in the August, 1984 release of PC DOS 3.0, a fact apparently … Continue reading

Posted in Development, DOS | 35 Comments


Prior to 1991, Microsoft did not sell MS-DOS to end users directly. Although MS-DOS 3.2 (1986) and later was available to system builders as a “packaged product”, most PC users would get an OEM version of MS-DOS with a new … Continue reading

Posted in Development, DOS, Microsoft | 7 Comments

Watcom Win386

When Windows 3.0 came out in 1990, the press loved it and users bought it in droves. Unfortunately, technically it was at best a step sideways, and Windows 3.0 was the cause of many sleepless nights for application developers. Even … Continue reading

Posted in 386, Development, Windows | 9 Comments

Kernel Debugging with VirtualBox

Virtualization readily lends itself to debugging of low-level code that is difficult to analyze in conventional environments. It is also convenient for kernel debugging which would otherwise require two separate systems or at least a separate serial terminal. OS/2 Setting … Continue reading

Posted in Development, OS/2, VirtualBox | 2 Comments

Retro development with aclock

In the past few days, I embarked upon a project to port Antoni Sawicki’s aclock, a small text-based clock program (aclock stands for analog clock), to 16-bit Windows. While aclock itself has been ported to over 150 platforms, it is a … Continue reading

Posted in Development, PC history, Windows | 13 Comments