Initialization of the stream descriptor
After your type-specific stream-open function has prepared the arguments for the mi_stream_init() function, it must call mi_stream_init() to initialize the stream descriptor.
Tip: Whether the mi_stream_init() function
actually allocates the stream descriptor depends on the value of its
third argument. For more information, see The stream descriptor.
The stream descriptor, MI_STREAM, holds information about the data stream such as the data and its seek position. For the most current definition of the MI_STREAM structure, see the mistream.h header file.