Re: Pointer Marshalling quesiton

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Well, I guess I'm out of practice on advanced IDL...
When I think about it, this is the same situation as with the
IEnumXXX family of interfaces.

One solution would be to use a [local]/[call_as] pair of
methods. Pass a stack variable to always receive the
interface pointer in your proxy shim and only return it to
the caller if it passed non-NULL pointer, otherwise release
it. I've posted local/call_as sample code in the past - you
may want to search the archives on Google groups.

The above solution is not very elegant I admit, since it still
involves interface pointer marshling. You may prefer to use
[wire_marshal] instead, though I have no direct experience
with that method of argument marshaling to advise you.

--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@xxxxxxxx
MVP VC FAQ: http://vcfaq.mvps.org
=====================================

"jonathannah" <jonathannah@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:632242B4-6E79-474F-93EE-6EA0F5AEF4BB@xxxxxxxxxxxxxxxx
Refer to the original post. The parameter is [out] IUnknown** ppUnk.
Midl
will not allow you to specify unique or ptr modifier. it gives a compile
error.

error MIDL2121 : [out] only parameter must not derive from a top-level
[unique] or [ptr] pointer/array : [ Parameter 'ppUnk' of Procedure 'Bar'

"Alexander Nickolov" wrote:

Just add the [unique] attribute. The default is [ref]. Note it works
for [out] pointers too, not only [in, out]. [ptr] will do as well, but
it's heavier on the marshaling since it checks for pointer aliasing.

--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@xxxxxxxx
MVP VC FAQ: http://vcfaq.mvps.org
=====================================



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