[Vm-dev] An event driven Squeak VM

[David T. Lewis]

On Thu, Nov 12, 2009 at 05:48:52AM +0200, Igor Stasenko wrote:
> 
> 2009/11/12 David T. Lewis <lewis at mail.msen.com>:
> >
> > On Wed, Nov 11, 2009 at 09:16:44PM +0200, Igor Stasenko wrote:
> >>
> >> Instead, why not expose the new VM abilities to language, so one could
> >> tell that specified callout should use a specified thread. Something
> >> like:
> >>
> >> threadHandle := Smalltalk currentThreadId.
> >
> > It is not hard to make these things accessible in the image, for example:
> >
> > ??OSProcess thisOSProcess pthread ==> a ByteArray(240 166 184 224 255 255 255 255)
> >
> > (this on a 64-bit platform, hence the 8-byte handle)
> >
> 
> its not really matters what object represents the thread handle (it
> could be simple smallint).
> And surely, its not that hard to expose some thread-aware API to
> language level, given that VM _is_ thread-aware.
> But by not exposing it, we losing another lever of control, using
> which we could write a sophisticated software,
> purely in smalltalk without getting down at C level.
> That's what i ment to say.

Yes I think that I understand your meaning. I was trying to agree
with you ;-)

Unix, Windows, and Mac have similar (but not identical) thread models,
and these can be made available to the image as you suggest. Getting
the cross-platform semantics right may be difficult but I am sure that
it can be done. And yes, the VM must be aware of the threads in order
to expose them to the image in a useful way.

Dave