Is MS-DOS, PC DOS and DR-DOS vintage enough to count?

[Eric Smith]

On Sun, Jul 31, 2016 at 12:21 PM, jim stephens <jwsmail at jwsss.com> wrote:
> I used Windows 95 for dos multitasking.  Windows 95 booted the processors
> into real mode dos, then ran the windows system out of that base dos much
> like Windows 3.1 had.  As such, the dos boxes all shared actual access to
> the real mode assets of the processor.
>
> Windows 98 switched to protected mode almost immediately on boot, and all
> the dos boxes were synthesized in virtual 8086 mapped mode, and had no
> underlying booted dos environment.

Both Windows 95 and Windows 98 do what you describe for Windows 98.
Both 95 and 98 can boot to DOS only, in real mode, but then you don't
get any GUI. In both 95 and 98, when you run the GUI, any DOS programs
you run are in virtual 8086 mode.

I know more than I really want to about this, because at one job I had
the misfortune of having to write VxDs to provide services to those
DOS windows, specifically because they couldn't run normal real mode
drivers to talk to hardware.