Use the mmioGetInfo function to get information on a file I/O buffer, such as the buffer size and address. The mmioGetInfo function has the following syntax:
UINT mmioGetInfo(hmmio, lpmmioinfo, wFlags)
The hmmio parameter specifies the file handle for an open file.
The lpmmioinfo parameter specifies a far pointer to a MMIOINFO structure that mmioGetInfo fills with information on the file I/O buffer.
The wFlags parameter specifies options for the operation. Currently, there are no options for mmioGetInfo.
The return value is zero if the operation is successful; otherwise, the return value specifies an error code.