Re: [MIT-Scheme-devel] non-recursive mutexes

[Arthur A. Gleckler]

On Monday, June 8, 2015, Taylor R Campbell <address@hidden> wrote:

 

>    Saying "don't rely on it, it's not documented" in reference to an
>    essential service is basically saying "our system is an unfinished
>    toy, we're sorry you decided to use it".
>
> That is basically true of the thread system at least.

Yes, that's fair.

 

> I've reverted the change, and added a WITH-THREAD-MUTEX-LOCK that is
> just a dynamic-wind of LOCK-THREAD-MUTEX/UNLOCK-THREAD-MUTEX, which
> already rejected recursion.
>
> (The revert could conceivably be cherry-picked into the release-9.2
> branch for a 9.2.1 release.)

Thanks.

I'm actually running tip-of-tree, so this is just fine for me.

 

> I still strongly advise designing your locks to avoid recursion: in
> almost all cases it will make reasoning about and understanding your
> program easier; in the few cases that remain you probably need other
> semantics anyway.

I still intend to look over the code to see what I can do cleanly.