Sent to a MIDI output device driver to request the current volume level setting for a device.
MMSYSERR_NOTENABLED | The driver failed to load or initialize. |
MMSYSERR_NOTSUPPORTED | The driver does not support changes to volume level. |
and the low-order word contains the left channel setting. A value of 0 is silence, and a value of 0xFFFF is full volume. If the driver does not support both left and right channel volume changes, it returns the volume in the low-order word.
Only drivers for internal synthesizer devices can support volume level changes. Drivers for MIDI output ports should return a MMSYSERR_NOTSUPPORTED error for this message. Support for volume level changes by internal synthesizer devices is optional. However, if a driver supports changes to the volume level with the MODM_SETVOLUME message, it must support queries with the MODM_GETVOLUME message.
MODM_SETVOLUME