Re: [Caml-list] Has the thread cancellation problem evolved ?

[skaller <skaller@users.sourceforge.net>]

On Tue, 2007-08-28 at 11:12 -0400, Brian Hurt wrote:
> Robert Fischer wrote:
> 
> > Brian Hurt wrote:
> >
> >> So what happens if I throw an infinite loop into an exception handler?
> >
> > Now, my experience with .Net is somewhat dated, but I'm pretty sure it 
> > re-hangs on your loop, and signaling another abort will break out of 
> > your loop and continue up the chain of exception handlers.  At least 
> > once upon a time, there was a very large business which I worked for 
> > that did a lot of concurrent .Net work, and the standard solution was 
> > to keep signaling the abort until the thing finally died.
> >
> > ~~ Robert.
> >
> >
> Until you get someone "clever", who does something like (in Ocaml):
> 
> let rec do_my_work () =
>     try
>        do_a_bunch_of_work ()
>     with
>     | Thread_abort_exception ->
>        (* Ack!  Someone tried to kill me!  I refuse to die! *)
>        do_my_work ()
> ;;
> 
> I suppose eventually you'd blow stack.
> 
> Then, there's the what-if:
> 
> let rec example () =
>     try
>        do_a_bunch_of_work ()
>     with
>     | Thread_abort_exception ->
>        raise (Invalid_arg "Ack!  They got me!")
> ;;
> 
> i.e. what happens if my catch expression raises another (different) 
> exception?
> 
> Not to mention the fact that this solution requires a rather intrusive 
> change to the run time, and a special exception which behaves 
> differently from every other exception.

That's when you have "ThreadReallyAbort" exception .. :))


-- 
John Skaller <skaller at users dot sf dot net>
Felix, successor to C++: http://felix.sf.net