Re: Threads docs updated in CVS

From: williamkempf_at_[hidden]
Date: 2001-08-15 19:32:15

--- In boost_at_y..., "Alexander Terekhov" <terekhov_at_d...> wrote:
> 
> >    I note the clever semantics: this call would have to
> > throw an exception if the thread had been detached.
> > But there's no call to detach a thread, so it cannot happen:
> > threads are detached simply by not calling join.
>   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> 
> really? without ref.counting? i do not understand this.
> can you explain this?

Unfortunately, to implement this correctly on top of pthreads I think 
we're going to have to ref-count.  Not in the same manner as you do 
with a thread_ref concept, but it's still going to need to be done.  
The biggest problem I see to getting this right is in not knowing 
precisely what POSIX defines as the result of calling join() on a 
thread that's already been joined or detached.  If it's undefined 
behavior then I'm going to have problems with "adopted" threads.  
We'll have to discuss what the appropriate design/implementation will 
be in that case.  Can you enlighten me on this issue?

Bill Kempf