Ditroff and Sun-4s (and lots of other machines)

[steve at umiacs.umd.edu]

The biggest problem that I know about is that ditroff (or the version we
have, at least, which probably isn't pure AT&T) wants to do varargs-like
stuff, but doesn't use varargs to do so.  Look in troff's n1.c at the
fprintf and sprintf routines, and change them to use varargs.  If you want
my diffs I can probably scare them up.  They may or may not drop right
in...

While you're at it, look at the caseev routine in n5.c (I think it is).
The way troff saves and restores environments is amusing, even if it
shouldn't be looked at on a full stomach.