[omniORB] Do _narrow() always result in net traffic?

[Gary D. Duzan]

In Message <Pine.LNX.4.04.9911030701290.12054-100000@disks.tcnet.eu.org> ,
   Michael Loftis <zop12@mindless.com> wrote:

=>
=>
=>On Wed, 3 Nov 1999, Haarek Ryeng wrote:
=>
=>> I'm replying to myself, as I think I found the answer.
=>> 
=>> After browsing the omniorb code, and verifying it with another
=>> orb
=>> (Orbacus for java), I found that the _narrow() call will only
=>> ask the remote object if the cast qualifies for a class cast
=>> exception.
=>> 
=>> So - there is practically no overhead in calling _narrow()!
=>> 
=>> -Haarek Ryeng  (thinking loud)
=>
=>Shoot me if I'm wrong but CORBA 2.3 deprecates _narrow() in favor of
=>_downcast()
=>
=>Same function essentially, but _Downcast() I think specifies other
=>prototypes.

   A quick glance at the spec shows that _downcast() is associated
Valuetypes, which are used for Objects By Value. _narrow() is still
the way to convert an object reference with a base interface type
to an object reference with a derived interface type.

					Gary Duzan
					GTE Laboratories