Introducing a cmp() operation

Bernhard Kauer kauer at
Wed Jun 15 15:53:49 CEST 2005

> > There are two ways how B could get its capability. Either B asks C to give
> > them, or A asks C to send one (of the capabilities it has from C) to B.
> > 
> > Both operations work out of the box. A and B do not trust each other and C do 
> > not need a cmp().
> I have to say I am at a loss how I can explain it further.

Perhaps we could discuss this offline e.g. via IRC.

> Here a summary: A can not ask C to send one, because this
> would either mean C has to make a blocking call to B, or B has to make
> a blocking call to A _and_ trust A to forward the request to C.  B
> really wants to make sure that it gets its own new mapping of the
> capability from C, and not from A.

How does it get the capability the first time?


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