How do you identify VAX/PMAX cpu's from software?

[George Robbins]

In article <1242 at riscy.dec.com> frank at croton.DEC.COM (Frank Wortner) writes:
> In article <40619 at bbn.COM>, fkittred at bbn.com (Fletcher Kittredge) writes:
> > In article <105 at asihub.UUCP> dan at asihub.UUCP (Dan O'Neill) writes:
> > > Is there a way to determine the class of a VAX or PMAX cpu under
> > > Ultrix?...
> > 
> > Well, I don't have access to all of these systems, so this is a guess.  Try
> > the uname() system call and check the resulting structure...
> 
> Fletcher, you are right.  Ultrix uname does exactly the minimum you describe.
> Unfortunately, it does not descriminate amoung the various CPU implementations
> That is, uname will say that the machine is a VAX, but nothing more.  It could
> be a 780, 3600, or whatever.  I'm afraid that bit-twiddling of magic words
> obtained from the kernel is needed to get more information.

Not too mysterious, the kernel variables _cpu, _cpu_subtype and mayhaps
_cpu_sub_subtype seem to be the basic story.  Values for cpu and subtype
show up in /sys/vax/cpu.h.  Of course there's no promise that the values
in a putative /sys/pmax/cpu.h don't overlap.

To emphasize an earlier point, this is not the kind of stuff that an
application should be looking at.  Unless there's some really good reason
for peeking under the skirts, the application should be insensitive to
cpu type or should a least view the matter as on of attributes rather
than instances.

-- 
George Robbins - now working for,	uucp: {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing	arpa: cbmvax!grr at uunet.uu.net
Commodore, Engineering Department	fone: 215-431-9255 (only by moonlite)