Ack to both of you. Thnx.

----- Original Message -----
> On Mon, Jan 09, 2012 at 09:40:55AM +0000, Gordon Sim wrote:
> > On 01/06/2012 10:58 PM, William Henry wrote:
> > >
> > >I'm curious about the following:
> > >
> > >1) Why do you need to explicitly set the receiver capacity in
> > >order to receiver messages? You'd think that be default you'd not
> > >have to set this.
> > 
> > You don't. The capacity controls the number of 'prefetched'
> > messages
> > the library will accept, i.e. messages delivered by the broker
> > before - and in anticipation of - application calls to fetch().
> > 
> > The default is to have no prefetch, which means the broker will
> > only
> > deliver a message in response to an explicit fetch() call. The
> > reason for this default is that it gives the most intuitive
> > behaviour in many cases and so is good for exploring/experimenting.
> > (Messages aren't hidden in prefetch queues anywhere).
> 
> One language-specific difference is that, with the non-blocking I/O
> extension for Ruby, the default capacity on a Receiver is 1 rather
> than
> 0.
> 
> > However, if you are using next_receiver() to service several
> > receivers, then you do need messages to be delivered before you
> > call
> > fetch() (since you don't know which of them will have messages) and
> > so in that case you do need to set capacity to some value greater
> > than zero.
> 
> --
> Darryl L. Pierce, Sr. Software Engineer @ Red Hat, Inc.
> Delivering value year after year.
> Red Hat ranks #1 in value among software vendors.
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> 
> 

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