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SV: JCSP, CSP Networking, and other some other points

Not having read all the words this morning..

How about using channel output in guards?
I work with Promela at the moment, it is VERY nice!
I know the transputer designers had their reasons to rule this out (was it the distributed architecture and fault modes?). How about a new keyword: DEAD?

ALT -- will send on any picked channel if not full or receivers
  old_occam_channel ! data
    ...  sorry
  new_occam_channel ! data
    ...  good!
  DEAD ? channel_index
    .... disconnect dead channel
  TRUE & clock ? AFTER 1985 PLUS 24
    ...  on time to do this now

especially when a channel has capacity, and sooner or later will block.
Does JCSP have this?

Med vennlig hilsen / sincerely
Øyvind Teig

Øyvind Teig
Senior dev.eng./utviklingsingeniør, M.Sc.
Autronica Fire and Security AS
A UTC Fire & Security Company
Tlf: +47 7358 2468 
Fax: +47 7358 2502
Mob: +47 9596 1506
home.no.net/oyvteig/pub - Publications


> -----Opprinnelig melding-----
> Fra: Mailing_List_Robot [mailto:sympa@xxxxxxxxxx] På vegne av 
> Ruth Ivimey-Cook
> Sendt: 25. februar 2009 01:06
> Til: occam-com@xxxxxxxxxx
> Kopi: Andrzej Lewandowski; 'Adam Sampson'
> Emne: Re: JCSP, CSP Networking, and other some other points
> Andrzej Lewandowski wrote:
> > Interesting. But... Occam, transputer, Kroc, all ARE THINGS OF THE 
> > PAST. Why you are playing with dead bodies instead of using your 
> > talent and knowledge to address problems that are current?
> >   
> I'm finding it hard to answer this thread - there are so many 
> conflicting ideas and requirements as Andrzej's note shows. 
> His comment reminds me of the old adage "A people who forget 
> their history are doomed to relive it". There are indeed in 
> occam and the transputer many ideas that are just as relevant 
> to today's world as ever. For some details see my conference 
> paper "//Legacy/ of the /transputer"/. 
> /However, there is a perception problem: that because (for 
> mostly commercial reasons) the transputer processor itself 
> "failed"**, that occam and the transputer were necessarily a 
> Bad Thing and to be condemned en-masse. This is unfortunate.
> I can see that the current demand for multi-core systems is a 
> great opportunity for CSP patterns to be used, and agree that 
> without significant penetration into the mindset that will be 
> lost. Perhaps this is an area that WoTUG can spend some money 
> - out and out advertising and sponsorship? Anyway, the other 
> side of the coin is that people are wedded to their existing 
> ideas and systems, sometimes by commercial necessity.
> The main barrier I have at my own workplace is that pretty 
> much all of the >1 million line core codebase of the software 
> is written in plain old C - and mostly to C89 standards - and 
> there is a significant portability requirement.  Some, in 
> outlying areas, is in C++ or Java. 
> New languages like C# and Ruby and Python are nowhere in sight.
> The consequence is that from a work viewpoint I'm very 
> interested in where a self-contained C-language CSP threads 
> library might go, but bring C++ in and I lose interest again.
> If we could come up with a serious competitor to the pthreads 
> library, written in portable C, that would be wonderful. If 
> it had versions in 
> Embedded-C++ and C# that would be even better. I'm not convinced that
> Java is a platform that needs CSP in the same way, but I 
> guess others are, so add in Java if you wish.
> Regards,
> Ruth
> P.S. I am (slowly) writing a new book describing occam-pi; at 
> present it's about 100 pages of an early draft of the core 
> language. I'm interested in feedback - if you would like to 
> see it please write and ask.
> **there are still transputers buried inside an awful lot of 
> the set-top boxes of the world.
> > -----Original Message-----
> > From: Mailing_List_Robot [mailto:sympa@xxxxxxxxxx] On 
> Behalf Of Adam 
> > Sampson
> > Sent: Tuesday, February 24, 2009 12:50 PM
> > To: occam-com@xxxxxxxxxx
> > Subject: Re: JCSP, CSP Networking, and other some other points
> >
> > Bob Gustafson <bobgus@xxxxxxx> writes:
> >
> >   
> >> I rather enjoyed reading Geraint Jones's two books on Occam. The 
> >> latest, with Michael Goldsmith - "Programming In Occam 2 (2nd 
> >> Edition) (Paperback)" is available on Amazon.
> >>     
> >
> > Geraint Jones has made an updated version available for free online:
> >   
> > 
> http://www.comlab.ox.ac.uk/people/geraint.jones/publications/book/Pio2
> > /
> >
> > The KRoC and Transterpreter implementations of occam-pi are 
> > open-source and available for a variety of operating 
> systems. KRoC is 
> > included with some Linux distributions, but it's under active 
> > development, so you're probably better off downloading the 
> latest version from us:
> >   http://projects.cs.kent.ac.uk/projects/kroc/
> >
> > The examples from the book will work directly in KRoC provided you 
> > wrap them in an appropriate top-level process (e.g. "PROC 
> main (CHAN 
> > BYTE
> > out)") -- but the extra facilities available in occam-pi 
> over occam 2 
> > can be used to simplify a lot of the code.
> >
> >