[comp.lang.smalltalk] Bad-event-type notifier appearing sometimes

gupta@prlhp1.prl.philips.co.uk (Ashok Gupta) (12/19/89)

When I run my Smalltalk image, I *sometimes* get a "bad event type" 
notifier.  This happens at the very first cursor movement after
running the image.

The stack is as follows :-

   InputState(Object)>>error:
   [] in ImputState>>primWindowEvent:
   [] in BlockContext>>newProcess

In keeping with the very worst of software problems, the damned thing
in non-deterministic.  :-(

Can anyone help ?  (Please email if you'd rather not post).
-- 
Ashok "Ash" Gupta
Post : Philips Research Labs, Crossoak Lane, Redhill, Surrey, RH1 5HA, U.K.
Voice: +44 293 785544 ext 5647
JANET: gupta@prl.philips.co.uk  ARPA: gupta%prl.philips.co.uk@nsfnet-relay.ac.uk

moss@takahe.cs.umass.edu (Eliot &) (01/03/90)

You did not indicate which implementation of Smalltalk you were running!
Still, I can tell you this much. Smalltalk handles all input by having
asynchronous interrupts put a note of what happened (mouse movement, button
change, keyboard key down/up) in an internal queue and then noticing those
*events* slightly later. Thus, as far as the operating system is concerned,
Smalltalk is interrupt driven, but its internal structure is more like
polling. Anyway, the notifier is saying it's finding a event in this internal
structure that it does not understand. This sounds like a clear cut virtual
machine bug to me. The fact that it happens at the beginning suggests an
initialization problem or initial race condition. I'd say to get with your
virtual machine supplier on it. Good luck!			Eliot
--

		J. Eliot B. Moss, Assistant Professor
		Department of Computer and Information Science
		Lederle Graduate Research Center
		University of Massachusetts
		Amherst, MA  01003
		(413) 545-4206; Moss@cs.umass.edu

obrien@aerospace.aero.org (Mike O'Brien) (01/10/90)

I actually went peeking on this one and determined that the fellow must
have been running ParcPlace Systems V2.3.  I'd say the window system is
sending his VM a window event of a type it never heard of.  Answer:
time to get V2.5.  If you're running The Analyst, go into the failed
routine and plug the hole with bailing wire (unless The Analyst is
now running under 2.5; I haven't heard).
--
Mike O'Brien
obrien@aerospace.aero.org