Re: external events api

On Aug 3, 2011, at 1:59 PM, Marcus Crestani wrote:

Should've replied to this sooner, but I've been busy. I think we have a misunderstanding.

>>>>>> "RM" == Roderic Morris <[email protected]> writes:
> RM> It seems that this api has trouble with notes happening in quick
> RM> succession.
> 
> Yes, it is not guaranteed that every `s48_note_external_event' gets
> handled immediately.  That's why external code has to collect multiple
> external events and provide a mechanism for Scheme to obtain *all*
> occurred events that have not yet been obtained before.

I understand that. The problem is that some of those calls are *never* handled. I've left the process idling for quite a while without them being woken. Moreover, after the first time a thread fails to wake up, all subsequent calls to s48_note_external_event have no effect, even on brand new event ids.

> I took a quick look at your patch and I think you should try the
> following:
> 
> - In `process-terminated-children' you have to collect all terminated
>  children, e.g. put them in a list.
> 
> - In `really-wait-for-child-process' you have to obtain that list of
>  terminated children after `wait-for-external-event' returns.  Then,
>  process every terminated child by unblocking previously called
>  `wait-for-child-process', for example via the placeholder in
>  process-id.
> 
> This way you should not lose any terminated child.

This is basically going back to what was their before. The reason I'm changing the code to not block on a placeholder is because of the deadlock detection. If I block on a placeholder with only one thread running, it'll detect a deadlock. I want to use the wait-for-external-event stuff so that won't happen. The problem is not missing terminated children. I'm noting everywhere I should, but the notes are having no effect in certain situations (as the last email said).

-Roderic