Re: serial callout devices

Matthias Urlichs (smurf@noris.de)
16 Jun 1999 13:26:51 +0200

Riley Williams <rhw@MemAlpha.CX> writes:
>
> > I've got a short memory; just why are the cua devices officially
> > obsolete now? Why not just leave the cua devices in and avoid
> > years of `stty doesn't work on my machine anymore' reports.
>
Because they don't work. In Ye Olde Days, you had your getty(8) listen
on ttyS*, you did your callout on cua*, and the kernel did the locking
between the two.
That idea breaks like <insert_appropriate_comparison_here> when you try to
use mgetty to listen for calls, because it waits for RING and sends ATA and
waits for CONNECT and only _then_ you'll get a DCD signal.

Anyway, the default setting for ttyS* includes CLOCAL, so if all your
serial-abusing programs leave the port in the state they found it there
shouldn't be any problem in the first place.

> What for, when that's so easy to fix...
> Q> ln -s ttyS$Z cua$Z ; \

That's not a fix. For one, you'll get problems with locking.

-- 
Matthias Urlichs  |  noris network GmbH   |   smurf@noris.de  |  ICQ: 20193661
The quote was selected randomly. Really.    |      http://www.noris.de/~smurf/

-- 
Hope is the fawning traitor of the mind, which, while it cozens with a
color'd friendship robs us of our best virtue -- resolution.
                                -- Lee


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