A pointer to an MMFORMATINFO
structure that might have optionally set the fccIOProc field
(FOURCC code) or ulMediaType field (multimedia data type). These
two fields provide the search criteria for matching an MMFORMATINFO
structure. If both of these fields are NULL, then all I/O procedure
MMFORMATINFO structures are returned,
provided enough space is allocated for in the buffer pointed to by the pFormatInfoList
parameter.