[Ur] howto register cleanup which is neither uw_malloc nor transactional?

[Adam Chlipala]

I'm a bit confused by your message.  In my reply, I will assume that you 
are asking only about actions to be taken upon completion of request 
handling, despite the fact that you use the word "cleanup" which, in the 
Ur/Web runtime system, has a meaning which involves actions being taken 
before a request finishes.

Marc Weber wrote:
> This requires two callbacks:
> - one for decreasing the usage counter on Ruby objcets (similar to when
>    uw_malloc storage is freed)
>    (uw_register_transactional or uw_set_global could be abused ?)
> - one callback to clear the cache (eg of http requests) after a request
>    stops being executed which is called in all cases:
>      * retried too often, fatal, or success
>    

These both seem like straightforward uses of the "free" callback passed 
to uw_register_transactional().

BTW, "uw_malloc() storage" is never "freed," and there are no "counters" 
involved.

> Is there a way to run code on startup ?
>    

Yes.  Write something like:

task initialize = (* something of type [transaction {}] *)

The timing of this might not be quite what you expect, so let me know if 
you need a new task type that runs at different times.