In article <199409202057.QAA28014@duality.gnu.ai.mit.edu>,
Charles M. Hannum <mycroft@gnu.ai.mit.edu> wrote:
:    Anyway, is it so bad to output something during probe time?  A
:    break signal maybe?
:
: A break signal would not cause an interrupt.

However, a break would prevent anything transmitted from further affecting
the transmitter output, as a break signal overrides the normal serial output.

Be that as it may, it is possible to generate the interrupt without
transmitting anything; I do it in my driver. The question I have is: what is
the proper way to detect the interrupt in a probe routine?