Re: Boost.Threads - thread_desc concept

From: williamkempf_at_[hidden]
Date: 2001-06-29 11:10:22

--- In boost_at_y..., John Max Skaller <skaller_at_o...> wrote:
> Greg Colvin wrote:
> 
> > To be clear, just stopping a thread "out of nowhere" is
> > a bad idea, as there is then no way to get out of any
> > monitors it has entered.  Better is a way to throw an
> > exception on the thread, so as to let destructors run.
> 
> 	You did not meet the requirements.
> The thread is blocked. It cannot throw anything.
> 

This is not true.  Any operation that is a "cancellation point" can 
block until either the operation completes, in which case it returns 
normally, or until a cancellation occurs, in which case it throws.  
This is, in fact, the method taken by the J/Threads C++ library.  
This approach has other problems, though, and I've pointed them out.

> 	It is a core language issue whether destructors
> are run when a thread is cancelled.

Only if threads are a core language feature.  We're not discussing a 
change to the core language, we're discussing a Boost threading 
library.

Bill Kempf