DRV_QUERYMAPPABLE function

The DRV_QUERYMAPPABLE message queries for whether the specified device can be used by a mapper.

Parameters

• uDeviceID Specifies the ID of the target device.

• uMsg Caller sets this parameter to DRV_QUERYMAPPABLE when it calls xxxMessage to process this device message.

• dwParam1 Unused. Set this parameter to zero.

• dwParam2 Unused. Set this parameter to zero.

Return value

The xxxMessage function returns MMSYSERR_NOERROR if the device is mappable. Otherwise, it returns an appropriate error code.

Remarks

This message is valid only for the waveInMessage, waveOutMessage, midiInMessage, midiOutMessage, mixerMessage and auxOutMessage functions. The system intercepts this message and returns the appropriate value without sending the message to the device driver. For general information about system-intercepted xxxMessage functions, see System-Intercepted Device Messages.

When an application program opens a mapper instead of a specific audio device, the system inserts a mapper between the application and the available devices. The mapper selects an appropriate device by mapping the application's requirements to one of the available devices. For more information about mappers, see the Microsoft Windows SDK documentation.

Requirements

See also

auxOutMessage

midiInMessage

midiOutMessage

mixerMessage

System-Intercepted Device Messages

waveInMessage

waveOutMessage