Using clang_getInstantiationLocation()

The documentation for clang_getInstantiationLocation() suggests that the second parameter has to be a pointer to a CXFile (object), which will be set to refer to the given location. I couldn't find any way to create such a CXFile instance without initializing it to a specific value. Does it exist ?

In my context I have a CXCursor, from which I want to construct a source location in terms of (filename, line-number, column), and I'm not sure how I'm supposed to do that.

Thanks,
         Stefan