I'm still learning about using COM objects. I'm trying to figure out where the values of CLSID_FileOpenDialog and IID_IFileOpenDialog are defined: https://learn.microsoft.com/en-us/windows/win32/learnwin32/example--the-open-dialog-box I couldn't find them in the included header files.
From one example I saw, I figured that I'd need .c and .h files with the interface and class GUIDs, but I couldn't find any reference of them for online.