那是无类型指针的无类型指针变量，API函数定义中已经说明了((void **)和(LPVOID *)是同样的类型)。
STDAPI CoCreateInstance(
REFCLSID rclsid, //Class identifier (CLSID) of the object
LPUNKNOWN pUnkOuter, //Pointer to controlling IUnknown
DWORD dwClsContext, //Context for running executable code
REFIID riid, //Reference to the identifier of the interface
LPVOID * ppv //Address of output variable that receives
// the interface pointer requested in riid
);
