4.2 vs ULTRIX

[mark at tove.UUCP]

This question of the differences between 4.2 and ultrix gets asked
so much I am posting my answer:

We have both ultrix and 4.2 here.  There are three differences:
1. device drivers.  DEC fixed some of the bugs in the Berkeley device
drivers that talk to DEC devices, particularly the RA81 disk.  There
might be other differences here.
2. error logging.  Supposedly the console error messages are now
understandable to the DEC field reps.
3. documentation.  DEC gives you the 4.2 manuals pages all nicely organized 
and bound, but with crazy little disclaimers for pieces of the system
that are still vanilla Berkeley code and so DEC can't vouch for.
These disclaimers are to be ignored:  even `man 2 fork` says 'not supported
by digital'!

Oh, and another difference, support.  DEC will bring up Ultrix for you
as with any software install.  (We had them do this for us even though
we were much more experienced at than they were.  They did ok.) I
presume they even have upgrades (although we haven't seen any) and
phone consulting service (although we haven't tried them.)  Also, Ultrix
is (more or less) available for anything in the Vax line.
	-mark
-- 
Spoken: Mark Weiser 	ARPA:	mark at maryland	Phone: +1-301-454-7817
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