Multiplexed Special Devices

[Chris Torek]

In article <13869 at ulysses.att.com> smb at ulysses.att.com (Steven Bellovin)
writes:
>As several people have noted, multiplexor devices date to v7.  They were
>indeed quite buggy, though I know of a few uses for the 4.1bsd versions.
>The early BSD support for BLIT terminals ....

Let us not forget Gosling Emacs. :-)

>The driver had a lot of potential if only (a) it were better-documented,
>and (b) it worked...

The 4.1BSD version had two major bugs:

1) A race condition occasionally resulted in trashed file systems.  Easily
   fixed, but quite a problem.

2) Tty channels could not be properly disconnected and reconnected.  I
   forget exactly how this worked (or failed).

After fixing both of these, we used multiplexed files quite happily for
some years.  My version of Gosmacs still supports them (theoretically).
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 405 2750)
Domain:	chris at cs.umd.edu	Path:	uunet!mimsy!chris