From: clc5q AT cobra DOT cs DOT Virginia DOT EDU (Clark L. Coleman)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Privileged assembler instructions
Date: 4 Mar 1999 14:43:23 GMT
Organization: University of Virginia
Lines: 26
Message-ID: <7bm66b$9um$1@murdoch.acc.Virginia.EDU>
References: <7bhdtm$4g0$1 AT murdoch DOT acc DOT Virginia DOT EDU> <199903021958 DOT OAA24745 AT envy DOT delorie DOT com>
NNTP-Posting-Host: cobra.cs.virginia.edu
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

In article <199903021958 DOT OAA24745 AT envy DOT delorie DOT com>,
DJ Delorie  <djgpp AT delorie DOT com> wrote:
>
>You should be able to do this with the ring-0 version of cwsdpmi
>(cwsdpr0.exe) but you won't be able to run any memory managers (like
>qemm, 386max).
>
>> If I install DJGPP, will I be able to use the gcc inline assembler
>> under DOS (I am running DR-DOS 7.03) to run programs with privileged
>> instructions? I am doing architecture/compiler research, and it would
>> be nice to have access to performance counter and cache flush
>> instructions, etc., that cannot be used in Windows NT because they are
>> privileged. I am hoping that the lessened secutiry of DOS will permit
>> me to run my experiments via gcc under DOS.


Is there anything special I need to do to use the ring-0 version? (If
this can be answered through "info", just point me to it.)

One more question: running in this fashion on DOS, am I going to be
able to compile a program with an array that is about 8 MBytes in
size?

Thanks for the help. If I can get this all to work, I'll be happy to
send a donation.