My limited experience was that the Ultrix ufs was close enough to the "fat"
ufs (referred to as ffs) in 4.4 that it would work, to a point. The way I
used it was to "fsck -c" the Ultrix ufs file system from 4.4 and then
assume I could never touch it from Ultrix again, which seemed to be safe.

If you only have one drive and need to share it between Ultrix and BSD, you
can put BSD into unused partitions (the Ultrix disk label, that is). To be
safe, you should make sure the default partition table in rz.c matches the
Ultrix label (in case BSD can't figure out the Ultrix label) and then
disable the code that forces root to the "a" partition (in setroot()?).

If you don't want to wait for the a.out stuff to be fixed up, you should
be able to build a system from NetBSD sources using the Ultrix ld, so that
the executables are ECOFF. (The bad news is that you don't end up with a
working debugger and will have to hack together an ECOFF nlist(), to get
some handy utilities compiled. You can actually work around the nlist one
by snitching it out of the Ultrix libc.a, but it is a pain to do, cause you
have to pull over a whole bunch of other .o's out of the Ultrix libc that
it uses, as well.)

Hope this drivel is of some help and have fun with it, rick

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