notify_dispatch (correct

[Fernando Pereira]

In a previous message, I claimed that notify_dispatch seemed to work for
me to poll window activity in compute-bound code sections, contrary to
what Mark Weiser had suggested. In fact, our comments are both true, but
the circumstances in which the two solutions are appropriate differ.
Mark's solution, a call to select, which in its SunView definition calls
the notifier implicitly (see "Implicit dispatching" in the notifier
documentation), is required if the compute-bound code is itself being
called from the notifier, eg. from an event handler or interposer. In
these situations, notify_dispatch seems not to work. In contrast, if the
program never enters window_main_loop and the compute-bound code is thus
not being called from the notifier, notify_dispatch works correctly.
That's what we have been doing. 

Fernando Pereira
AI Center, SRI International
pereira at ai.sri.com