WORD waveOutGetVolume(wDeviceID, lpdwVolume)
This function queries the current volume setting of a waveform output device.
WORD wDeviceID
Identifies the waveform output device.
LPDWORD lpdwVolume
Specifies a far pointer to a location to be filled with the current volume setting. The low-order word of this location contains the left channel volume setting, and the high-order word contains the right channel setting. A value of 0xFFFF represents full volume, and a value of 0x0000 is silence.
If a device does not support both left and right volume control, the low-order word of the specified location contains the mono volume level.
The full 16-bit setting(s) set with waveOutSetVolume is returned, regardless of whether the device supports the full 16 bits of volume-level control.
Returns zero if the function was successful. Otherwise, it returns an error number. Possible error returns are:
MMSYSERR_INVALHANDLE
Specified device handle is invalid.
MMSYSERR_NOTSUPPORTED
Function isn't supported.
MMSYSERR_NODRIVER
The driver was not installed.
Not all devices support volume changes. To determine whether the device supports volume control, use the WAVECAPS_VOLUME flag to test the dwSupport field of the WAVEOUTCAPS structure (filled by waveOutGetDevCaps).
To determine whether the device supports volume control on both the left and right channels, use the WAVECAPS_VOLUME flag to test the dwSupport field of the WAVEOUTCAPS structure (filled by waveOutGetDevCaps).
waveOutSetVolume