2011/3/5 Georgi Petrov <gogothe...@gmail.com>:
> On Sat, Mar 5, 2011 at 2:48 PM, Kai Tietz <ktiet...@googlemail.com> wrote:
>> 2011/3/5 Georgi Petrov <gogothe...@gmail.com>:
>>> Hi,
>>>
>>> I have a quick question. I can't figure out something. I have the
>>> following COM function definition:
>>> STDAPI MFCreateVideoRenderer(REFIID riidRenderer, void ** ppVideoRenderer);
>>>
>>> The first parameter (riidRenderer) is Interface indentifier (IID) of a
>>> COM class. When calling MFCreateVideoRenderer, I want to pass a
>>> particular IID, for example IID_IMFMediaSink.
>>>
>>> In C++, I would write:
>>> MFCreateVideoRenderer(__uuidof (IID_IMFMediaSink), ...
>>>
>>> However, in C, this is not possible. The GUID of my desired interface
>>> (IID_IMFMediaSink) is
>>> 0x6ef2a660,0x47c0,0x4666,0xb1,0x3d,0xcb,0xb7,0x17,0xf2,0xfa,0x2c and I
>>> have defined it myself like this:
>>>
>>> DEFINE_GUID(IID_IMFMediaSink,
>>> 0x6ef2a660,0x47c0,0x4666,0xb1,0x3d,0xcb,0xb7,0x17,0xf2,0xfa,0x2c);
>>>
>>> Then how can I "convert" it to a suitable first parameter of
>>> MFCreateVideoRenderer? I've been stuck with this problem for 2 days
>>> and I really can't figure it out. Any help will be appreciated!
>>>
>>> Georgi
>>
>> Well, pretty easy. Just pass to this function the address of the GUID.
>> the __uuidof keyword in fact returns a const GUID * for C (for C++ it
>> is a const GUID &).
>>
>> Regards,
>> Kai
>
> Hi Kai,
>
> I believe that __uuidof() is C++ specific operator only. At least this
> is the information I got from various places. When used in C, I get
> "implicit declaration of function '__uuidof'".
>
> The REFIID parameter which my function expects is actually "const
> struct GUID * const", while DEFINE_GUID is of type "GUID". Can you
> give me with a simple one line cast of some sort, which actually
> works? I'm pretty lost.
>
GUID IDD_SomeId = { .... };
for C the argument would be then func (&IDD_SomeId);
If you are doing this with C++ uses then ((REFID) &IDD_SomeId, ...);
Kai
------------------------------------------------------------------------------
What You Don't Know About Data Connectivity CAN Hurt You
This paper provides an overview of data connectivity, details
its effect on application quality, and explores various alternative
solutions. http://p.sf.net/sfu/progress-d2d
_______________________________________________
Mingw-w64-public mailing list
Mingw-w64-public@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/mingw-w64-public
