instability in Berkeley versus AT&T releases

[John Mashey]

> > even if it uses stty, I'd say it's Bell that's in the unstable computing
> > environment business.
> 
> If you're referring to the S3 terminal driver, from Bell's standpoint they
> didn't break anything.  It's compatible with UNIX 2.0 (or PWB/UNIX 2.0 or
> whatever the hell the release before UNIX 3.0 was).  The trouble is that the
> release that went out the door before System III was V7, not UNIX 2.0, which
> means the S3 driver's backward compatibility with UNIX 2.0 is totally
> useless to anybody outside the former Bell System.

1) PWB/UNIX 2.0 was the release before, and before that was UNIX/TS 1.0
(Nov 78).  Both of these still had stty/gtty in section (2), with ioctl(3),
with everybody warned to switch over.

2) It is always worth remembering:
	a) Research versions of ANYTHING have no commitment whatsoever to
	upward compatibility (whether from ATT, UCB, or anywhere else).  Once
	they do that, the research content falls off pretty badly.  Back in
	the real old days when we got releases straight from 127, we were
	happy when something was upward compatible, but certainly didn't
	expect it.	
	b) Supported versions that do have such commitments must play by
	radically different rules, which make them take longer to do:
		1) Worry about major customers [for example, as I recall,
		the ioctl stuff came from CB/UNIX, or Operations Systems Unices
		in general, because the V6/V7 stuff wasn't quite enough.
		Remember that such Unices paid the bills for a long time.
		2) Never add anything that you not sure of lasting for a while,
		because you do have the commitment to keep it semi-forever.
		3) Work very hard on transition aids and strategies.
-- 
-john mashey
UUCP: 	{decvax,ucbvax,ihnp4}!decwrl!mips!mash
DDD:  	415-960-1200
USPS: 	MIPS Computer Systems, 1330 Charleston Rd, Mtn View, CA 94043