> > > Is this theory correct and are there any suggestions how to work around this problem (implementing timed execution of arbitrary code).
> > 
> > Arbitrary code? No way to make that happen. For specific cases: yes,
> > there are many ways to do it.
> I don't really need that for arbitraty code. Our tool calls a stub-function that executes C-code of a SAT-Solver. And I want to make sure, that this function stops after a certain timeout. Are there any suggestions?

Maybe this works:

- Create a new C function set_timeout_handler that defines the signal
handler. The handler is another C function timeout_handler.

- In O'Caml, only do:
  * block SIGALRM (so O'Caml never sees this signal)
  * Start the itimer

- Change the C code of the SAT solver as follows. Before it starts,
unblock SIGALRM, so this signal can be delivered. Then define an exit
with sigsetjmp.

- In timeout_handler, just siglongjump out of the solver to the
previously defined exit. SIGALRM should be blocked again, before
returning to O'Caml.

Complicated, isn't it, but if a signal is the only way to stop the
solver, the handler must be defined in C.

Gerd


> cheers
> 
> christian
> > 
> > Gerd
> > 
> > > 
> > > thnx in advance
> > > 
> > > christian
> > > 
> > > _______________________________________________
> > > Caml-list mailing list. Subscription management:
> > > http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list
> > > Archives: http://caml.inria.fr
> > > Beginner's list: http://groups.yahoo.com/group/ocaml_beginners
> > > Bug reports: http://caml.inria.fr/bin/caml-bugs
> > > 
> > -- 
> > ------------------------------------------------------------
> > Gerd Stolpmann * Viktoriastr. 45 * 64293 Darmstadt * Germany 
> > gerd@gerd-stolpmann.de          http://www.gerd-stolpmann.de
> > Phone: +49-6151-153855                  Fax: +49-6151-997714
> > ------------------------------------------------------------
> > 
> 
> _______________________________________________
> Caml-list mailing list. Subscription management:
> http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list
> Archives: http://caml.inria.fr
> Beginner's list: http://groups.yahoo.com/group/ocaml_beginners
> Bug reports: http://caml.inria.fr/bin/caml-bugs
> 
-- 
------------------------------------------------------------
Gerd Stolpmann * Viktoriastr. 45 * 64293 Darmstadt * Germany 
gerd@gerd-stolpmann.de          http://www.gerd-stolpmann.de
Phone: +49-6151-153855                  Fax: +49-6151-997714
------------------------------------------------------------