New JCSP release

[P.H.Welch@xxxxxxxxx]

Dear All,

I've put another JCSP release (1.0-rc4) in its usual place:

  http://www.cs.ukc.ac.uk/projects/ofa/jcsp/

This only has a few changes/corrections to some of the documentation files.

But it does include a new demo - MultiPong :-) - and an uprated version of
the Infect demo (which has more controls and interaction ... check out how
hard it is to fight Foot-and-Mouth when your culling policy is only 99%
effective ...).

The "Support Materials" on the website have been extended - indicated by
the "new" labels.

I'll decide to make this the *real* JCSP 1.0 release real soon now!

Some people have been wanting to shut down running processes - especially
the widget processes in jcsp.awt.  Closing down live threads is a mistake Sun
made originally in JDK 1.0.  They recovered by deprecating the Thread.stop
method ... but their documentation suggests it's safe to replace this by
polling a shared variable (!) or using/checking the Thread.interrupt
mechanism.  At least the latter can be made safe, although we do seem
to have to craft some clever code to make it so ... code that fits no
universally workable pattern?

Anyway, there *is* a standard mechanical way of safely shutting down CSP
networks ("Graceful Termination ...", proceedings of OUG-10).  Well, it's
safe and retro-fittable but doesn't half mess up your process code!  So,
I'd like some help in the best way to access this capability in JCSP -
any thoughts appreciated.

Maybe, I'll just make the jcsp.awt widgets terminate if anyone sends them
POISON on their configure channel.  That's easy and would keep those
currently raising the issue happy ... so maybe that'll go into the 1.0
real release ... along with the L-GPL (or Artistic) open source license ...
any preferences?

Peter.

PS. Don't forget to check out and register for CPA 2001 at Bristol
    (16-19 September, 2001):

      http://www.cs.bris.ac.uk/Events/CPA2001/
    
    A provisional timetable is published - abstracts of talks are coming ...