Re: new exec server protocol

[Marcus Brinkmann]

On Thu, May 22, 2003 at 09:50:22PM +0200, Niels Möller wrote:
> I also like the task-server to be as simple as possible, and I
> tend to think about it as a layer slightly _below_ libports.

In my mail I described that task handles can look like normal handles to the
outside but implemented simpler internal to the task server.  I don't expect
the task server to actually use what you call libports.

> Sorry, I meant task references. It was perhaps unnecessary to delve
> into implementation details, the interesting observation here is only
> that the normal state of affairs (except possibly when handles and
> references are in transit), A will have a reference to B if and only
> if B has a reference to A.

I am not sure this observation buys you anything, it is just too weird to
think about it that way.  If you only use one bit to record the A-B
relationship, what do you do if one side unilaterally releases the task ID
reference to the other task?
 
> I think the current model allows a task to hold references to other
> tasks, with out subscribing to notifications. Such tasks should poll
> for task deaths occasionally, but perhaps not very often.

Holding a reference for a long time makes only sense if you also want to
know about the task death.  If you don't do that, you are expected to
release the reference quickly.  Not sure if such a case is needed, though.

Thanks,
Marcus

-- 
`Rhubarb is no Egyptian god.' GNU      http://www.gnu.org    address@hidden
Marcus Brinkmann              The Hurd http://www.gnu.org/software/hurd/
address@hidden
http://www.marcus-brinkmann.de/