[gwbas1c]

Well, Windows / Mac / Linux needs the Bios (or whatever we call it today) to run.

If you can't call those "OS"s, than what really is an OS?

I guess it's turtles all the way down.

> almost every serious game is a complete more-or-less real time operating system

Games tend to have very different requirements and different demands from the OS; they tend to regulate the OS to being (mostly) a hardware abstraction layer. In the late 1990s and early 2000s, it was a lot harder to run games on Windows NT versus Windows 9x because DOS was a lot better at getting out of the way of games.

[jacquesm]

And I wrote that stuff in the 80's, when your typical 'OS' on a computer was much closer to what a BIOS is than an actual operating system. Usually the games were far more sophisticated in terms of what their internal services provided than the equivalent OS services. The most the BIOS usually did for you was to boot your game code, change graphics modes, handle the keyboard and read and write raw media. Everything else you had to do for yourself.

Today there are far more levels of abstraction, especially when you use the various 3D engines or other large frameworks. But essentially those have taken over the role of a lot of that OS-like code.