User-Mode Audio Driver Messages

The following table lists the messages that each driver entry point can receive. Messages are divided into those that the driver is required to support, and those that the driver can optionally support. Message definitions are contained in mmddk.h.

Entry Points	Required Messages	Optional Messages
auxMessage	AUXDM_GETDEVCAPS AUXDM_GETNUMDEVS	AUXDM_GETVOLUME AUXDM_SETVOLUME
midMessage	MIDM_ADDBUFFER MIDM_CLOSE MIDM_GETDEVCAPS MIDM_GETNUMDEVS MIDM_OPEN MIDM_RESET MIDM_START MIDM_STOP	MIDM_PREPARE MIDM_UNPREPARE
modMessage	MODM_CACHEDRUMPATCHES MODM_CACHEPATCHES MODM_CLOSE MODM_DATA MODM_GETDEVCAPS MODM_GETNUMDEVS MODM_LONGDATA MODM_OPEN MODM_RESET	MODM_GETVOLUME MODM_PREPARE MODM_SETVOLUME MODM_UNPREPARE
mxdMessage	MXDM_CLOSE MXDM_GETCONTROLDETAILS MXDM_GETDEVCAPS MXDM_GETLINECONTROLS MXDM_GETLINEINFO MXDM_GETNUMDEVS MXDM_OPEN MXDM_SETCONTROLDETAILS	MXDM_INIT
widMessage	WIDM_ADDBUFFER WIDM_CLOSE WIDM_GETDEVCAPS WIDM_GETNUMDEVS WIDM_GETPOS WIDM_OPEN WIDM_RESET WIDM_START WIDM_STOP	WIDM_LOWPRIORITY WIDM_PREPARE WIDM_UNPREPARE
wodMessage	WODM_BREAKLOOP WODM_CLOSE WODM_GETDEVCAPS WODM_GETNUMDEVS WODM_GETPOS WODM_OPEN WODM_PAUSE WODM_RESET WODM_RESTART WODM_WRITE	WODM_GETPITCH WODM_GETPLAYBACKRATE WODM_GETVOLUME WODM_PREPARE WODM_SETPITCH WODM_SETPLAYBACKRATE WODM_SETVOLUME WODM_UNPREPARE

Note: If you are writing a driver for a waveform device that supports compressed data formats, your driver must also support some of the Audio Compression Manager (ACM) messages. For further information, see Providing ACM Support in Device Drivers, which is contained in the Audio Compression Manager Drivers chapter.