ttyd0/cuad0 - why is there still this duality ?

[Nicolas Rachinsky]

* Sam Leffler <sam at errno.com> [2005-01-24 19:29 -0800]:
> M. Warner Losh wrote:
> >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.

But can you use the device for dialing out while an application is
waiting in a select on it?

Nicolas