An application can use the mmioQueryFormatCount function to query the number of formats supported. It can then call mmioGetFormats with the correct size of pFormatInfoList to obtain descriptive information about the file formats supported by currently installed I/O procedures. This listing will assist you in finding out which data types can be output to a device. You can also use mmioGetFormats to query the number of file formats supported. To allocate the buffer for the file formats supported, multiply the number of formats by the size of the MMFORMATINFO structure. (The MMFORMATINFO structures are all the same size.)