what happened to /dev/cuaa0

[Dan Nelson]

In the last episode (Sep 21), Anton Shterenlikht said:
> After reading Section 22.2.2.2.2 of the Handbook my understaning is
> that the same serial port can be addressed as either /dev/ttydN or
> /dev/cuadN. Is that correct?

Yes.
 
> I'm confused by the "Call-in" - "Call-out" terminology. I have an
> external modem connected to 1st serial port, and I use it as
> /dev/ttyd0. Does it mean it becomes a call-in device?

The only real difference between the devices is that call-in devices
block when you try to open them, and unblock when carrier is detected
(i.e. if someone calls into the modem and it's set to auto-answer).
When a process is blocked, another process can "steal" the port by
opening the callout device, which doesn't block.  It's described in the
sio manpage, too.

-- 
	Dan Nelson
	dnelson at allantgroup.com