Sorry, Udo, for quick response. I think you can do that with Pharo without polling. You just use semaphores (which directly signaled by OS+VM). I am not sure about if everything in VM (usb/midi /etc) uses non-blocking i/o out of the box, but if you really really want to hake it and ready to pay for it (in terms of own time (or somebody else's ;) )) i do not see any impenetrable barriers there.
-- Best regards, Igor Stasenko.
