Re: [boost] [futures] Request for Comments

From: Alexander Terekhov (terekhov_at_[hidden])
Date: 2005-08-19 07:02:32

Andrey Melnikov wrote:
[...]
> > How do you cancel threads?

You use pthread_cancel() and rely on mandatory cancel delivery to 
"shall occur" cancellation points. Victim threads shall also be
prepared to "may occur" delivery for optional cancellation points
and async-cancel regions (when cancellation is enabled, of course).

> 
> The explanation in the FAQ doesn't explain the problem in details.
> Here's a brief example:
> 
> bool f1(X x)
> {
>         X * y = new X;
>         // if f1() is aborted at this point
>          // *y won't be deallocated
>         delete y;
>         return false;
> }

Your f1() is clearly async-cancel-UNSAFE as written. So what?

regards,
alexander.