ttyd0/cuad0 - why is there still this duality ?

[Sam Leffler]

M. Warner Losh wrote:
> In message: <20050124124250.A27718 at pix.net>
>             "Kurt J. Lidl" <lidl at pix.net> writes:
> : Having seperate dialout and dialin devices really are just a kludge
> : for having the kernel doing locking that could be done in userland
> : code.
> 
> That's not why they are there.

Maybe now; that's not why they were added originally.

> 
> : Just because FreeBSD does this the same way it's been done on
> : BSD-ish systems for the last 15 years doesn't mean there isn't a
> : better way of doing it.
> 
> That's uncalled for.
> 
> The real reason that they are there is that ttyd waits for carrier
> detect, while cua doesn't.

Non-blocking open followed by block on read/write and/or select dealt 
with that long ago.

	Sam