Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!sdd.hp.com!hplabs!pyramid!csg
From: csg@pyramid.pyramid.com (Carl S. Gutekunst)
Newsgroups: comp.sys.sequent
Subject: Re: Dial-in/Dial-out on same tty port
Message-ID: <142825@pyramid.pyramid.com>
Date: 29 Jan 91 16:13:18 GMT
References: <31108@sequoia.execu.com> <119792@uunet.UU.NET> <12334@sybase.sybase.com>
Distribution: usa
Organization: Pyramid Technology Corp., Mountain View, CA
Lines: 18

>Dialin/dialout has been basic functionality in BSD UNIX for at least 10 years;

How? Acucntrl didn't appear in any software *from Berkeley* until 4.3BSD,
which is barely five years ago. And acucntrl is a very poor solution, as it
requires cooperation from the out-calling task. It was also disaster prone,
and the BSD version didn't run on anything except a VAX. Note that versions of
acucntrl have been done for most BSD-ish boxes, although not by the vendors. 

HoneyDanBer UUCP comes with the magic uugetty, although it doesn't work very
well. (Security problems, doesn't work with all modems, fussy about the modem
options, and so on.) Systems VR3.1 included uugetty.

The best solution -- the Chris Torek ACU device, implemented by Sun -- is a
little more than two years old. To the best of my knowledge, Sun is the only
UNIX vendor that supports this. It's a little tricky on multi-processor
systems, since you can get race conditions between last close and first open.

<csg>