> interesting, that might be worth implementing.
>

Maybe.


> the alternative would be to send the reading process a note to
> interrupt the blocking syscall.
>

Actually, it my 'plan B'... ;)

the closer proc should just send the note and not close the fd.
> and the reader proc should close the fd once he's out of the
> reading loop.
>

Exactly!

Well, I would prefer a solution with 'hangup', it seems cleaner to me...
...but since it is not implemented in UDP driver, I will implement the note
based solution.

Pavel


Pavel