generating code to run multiple targets

[Guy Harris]

>>From the SunOS manpage MACHID(1):
>>  sun, iapx286, i386, m68k, pdp11, sparc, u3b, u3b2, u3b5, u3b15, vax
>>  The list of processors implies that this is not a Sun-ism, but comes
>>with standard BSD 4.x.  What have I been missing from this discussion???
>
>There is a core list: u*b*, vax, pdp11 and maybe a couple of others.

Yup.  The original poster inferred, incorrectly, that most of the items
in that list came with standard 4.xBSD.  The only ones that did were, I
think, "pdp11" (maybe), "vax" (definitely), and possibly "tahoe"
(4.3-tahoe).  Sun added some themselves ("m68k", "sparc"), picked up
some from various 3B flavors of S5 ("u3b*"), and picked up others from
descriptions of the AT&T 80286 and 80386 UNIX versions ("iapx286",
"i386") - no, even though they're AT&T versions for the 80*86, the
commands are *not* in AT&T's 3B versions.

However, the core list, meaning the intersection of all the sets of such
names provided by all manufacturers, is smaller than the one you list. 
u3b* come with S5, but not all vendors have them; Sun picked them up in
SunOS 3.2.  My guess is that the core list is, *at most*, "vax" and
"pdp11"; it may well be the empty set.