Here in alt.msdos said:
NT ran dos programs in its OS/2 subsystem.
David, simply repeating something multiple times does not make it true,
even though a USENET search shows that you've been making similar types
of (also seemingly unsupported) statements in various newsgroups for
some time.
It would lend some credibility to your position if you cited an actual
source for the above assertion, or if you clarified what you meant by
"running in the OS/2 subsystem", since at its face that statement makes
no sense at all.
A native "OS/2 environment" uses a flat memory model and does not run
DOS programs at all, similar to a Linux environment that doesn't have
a copy of DOSEMU present. Its native API is radically different from
that provided by MS-DOS, PC-DOS, or their kindred.
To run DOS software, OS/2 must also emulate DOS, as the 32-bit OS/2 2.0
and later does with its MVDM subsystem, and as Linux can in a somewhat
less sophisticated manner using DOSEMU or DOSBOX.
The native OS/2 prompt in modern OS/2 variants runs 16-bit and 32-bit
native OS/2 programs directly, but it has to spawn a VDM as a separate
process (which runs completely independently) to run a DOS program.
I don't know how the old OS/2 1.x ran DOS programs. Perhaps Windows NT
did something similar in its OS/2 subsystem, actually invoking a 16-bit
OS/2 environment first and then a DOS environment when a DOS executable
was detected. I don't know. But then it wouldn't really be running in
the OS/2 subsystem at that point -- it would be running in a VDM.
An actual detailed explanation would be educational, at least to me.
Or... If you can't provide one, perhaps someone else can...?
