Last updated: 28 January 2004
A number of people have submitted comments, constructive criticism, and feedback since the first printing. Our thanks go to everyone who helped us weed out bugs and make this a better book. All the people who contributed are listed in the acknowledgments to our readers.
The C++ mapping for _var types is under-specified in CORBA 2.3
because it does not show how _var types for fixed-length
underlying types should work. On 10 January 2000, the OMG C++
Mapping RTF voted to clarify the situation by specifying the
mapping for _var types for
fixed-length underlying types. (Note that the implementation shown
is not binding in the sense that its internals may differ in each ORB;
however, the semantics must be the same.) The upshot of this mapping is that,
once initialized (which is always via a deep copy), a _var
variable for a fixed-length underlying type behaves like a value of the
underlying type.
The call to activate_object incorrectly passes the servant instead of the address of the servant. The call should read:
poa->activate_object(&ctrl_servant);
The second paragraph states that even for requests made locally, they must be dispatched on the POA's single thread instead of the caller's thread.
Different ORB vendors have interpreted the wording in the specification
differently, so the semantics of the SINGLE_THREAD_MODEL
policy with respect to collocated calls are currently under discussion.
Until this matter is settled in the OMG Core Revision Task Force, you
must assume that it is implementation-dependent whether the call is
dispatched on the POA's single thread or the caller's thread.