MSDOS apps on any platform of vista?

J

Jim Michaels

I am pretty sure no x64 version of any microsoft OS runa MSDOS
applications, but does the 32-bit version of any of the Vista family run
MSDOS applications?

and no, I am not talking about cmd.exe - I am talking command.com...
they are very different. command.com supposedly has the NTVDM behind it.
and I am told Vista doesn't have this (but that was on a x64 forum).

I need the straight facts.

no, I don't want to be offered emulators. I want to know what runs
plain on the OS without modification.

--

------------------------------------
Jim Michaels
for email, edit the address

"Because we do not understand the brain very well we are constantly
tempted to use the latest technology as a model for trying to understand
it. In my childhood we were always assured that the brain was a
telephone switchboard. ('What else could it be?') I was amused to see
that Sherrington, the great British neuroscientist, thought that the
brain worked like a telegraph system. Freud often compared the brain to
hydraulic and electro-magnetic systems. Leibniz compared it to a mill,
and I am told some of the ancient Greeks thought the brain functions
like a catapult. At present, obviously, the metaphor is the digital
computer." - John R Searls.
 
A

Andrew McLaren

Jim Michaels said:
I am pretty sure no x64 version of any microsoft OS runa MSDOS
applications, but does the 32-bit version of any of the Vista family run
MSDOS applications?
Click to expand...

Hi Jim,

Yes: 32-bit Vista can run 16-bit MS-DOS and Windows 3.x applications. The
NTVDM is present and fully functional in 32-bit Vista.

Like any program, a specific application may encounter some compatibility
problems under Vista. Writing to file locations like anywhere under the
\Windows directory, or under \Program Files, is tightly restricted under
Vista. This may cause problems for older applications. And as always, DOS
applications which attempt to directly address the hardware will fail when
running in the NTVDM; they need to request system services by calling DOS
interrupts instead. But, these limittaions have applied since NT 3.1, so
nothing new really.

On a purely anecdotal note: I keep a copy of Visicalc 1.0 (c.1981) which I
run on every new version of DOS and Windows, as a rough-and ready
compatibility guide. I'm glad to say Visicalc opens and closes files, and
even prints, when running on Vista! I've also helped a few users get their
legacy business applications running on Vista, by setting up codepage
support etc. Basically everything works pretty much the same as before.

As you note, 16-bit applications cannot run on 64-bit Windows (whether XP,
Server 2003 or Vista). This is a limitation of the hardware - the IA-32 VDM
instructions used by Windows' NTVDM just cannot run on a 64 bit processor
when the processor is in 64 bit Mode. If the 64-bit processor is running in
32-bit mode, then the VDM instructions are available (so, you can run DOS
apps on 32-bit Vista runing on a 64-bit CPU ... since nearly all new CPUs
are 64 bit anyway).

Hope it helps!
 
Top