Keyboard check under UNIX Sys V?

[George Robbins]

In article <7847 at sun.uucp> guy at sun.uucp (Guy Harris) writes:
>If somebody has evidence that S5R1 and S5R2 differ in the handling of
>MIN == 0 cases on *vanilla* S5 distributions (i.e., nobody made any changes
>to "tty.c" or "tt1.c"), I'd like to hear it.  Otherwise, the differences are
>probably a function of somebody "fixing" their S5 to work the way S3 did.
>In S3, TIME was *never* a timeout whose clock started when the read was
>performed; the clock started only when a character arrived.
>	Guy Harris {ihnp4, decvax, seismo, decwrl, ...}!sun!guy

I believe that the was a problem with the documentation for System III not
matching the semantics actually implemented in the 'real' System III.  Zilog
stumbled badly on this when they changed their tty driver to conform to the
manual between System III releases, and wouldn't change it back.  Then they
had to flip-flop again when they went to do a System V port.

I wouldn't be at all suprising for any of the early System V ports to actually
be using updated System III tty drivers, rather then starting from scratch.

At least unix isn't alone in this madness:  there are a lot of IBM 2780/3780
emulations that choke stiff on a missing block, becuase the IBM Bisync GI manual
gives an incorrect description of what to do on a block sequence error.

-- 
George Robbins - now working for,	uucp: {ihnp4|seismo|caip}!cbmvax!grr
but no way officially representing	arpa: cbmvax!grr at seismo.css.GOV
Commodore, Engineering Department	fone: 215-431-9255 (only by moonlite)