Windows Multimedia DDK (mddkqh.hlp) (Table of Contents; Topic list)
AUXDM_GETVOLUME
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AUXDM_GETVOLUME
 
        This message is sent to an auxiliary audio device driver to
        request the current volume level setting for a device.
 
Parameters
        DWORD dwParam1
            Specifies a far pointer to a DWORD location. The driver
            fills this location with the current volume level setting.
            The high-order word contains the right channel setting 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.
 
        DWORD dwParam2
            Unused.
 
Return value
        The return value is an error code, or zero (MMSYSERR_NOERROR) if
        the operation is successful. Possible error codes are:
 
        MMSYSERR_NOTENABLED
            The driver failed to load or initialize.
 
        MMSYSERR_NOTSUPPORTED
            Function isn't supported.
 
Comments
        Drivers do not have to support volume level changes. However,
        if a driver supports changes to the volume level with the
        AUXDM_SETVOLUME message, it must support queries with the
        AUXDM_GETVOLUME message.
 
See also
        AUXDM_SETVOLUME
 
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