The AUXDM_GETDEVCAPS message requests an auxiliary audio driver to return the capabilities of the specified auxiliary audio device.
Parameters
uDeviceId
Device identifier (0, 1, 2, and so on) for the target device.
uMsg
AUXDM_GETDEVCAPS
dwUser
Not used.
dwParam1
Pointer to an empty AUXCAPS structure. This structure is used to return the capabilities of the device. (The AUXCAPS structure is described in the Win32 SDK.)
dwParam2
Size of the AUXCAPS structure in bytes.
Return Value
The driver should return MMSYSERR_NOERROR if the operation succeeds. Otherwise it should return one of the MMSYSERR error codes defined in mmsystem.h.
Comments
A client sends the AUXDM_GETDEVCAPS message by calling the user-mode driver's auxMessage entry point, passing the specified parameters.
Typically, the user-mode driver calls DeviceIoControl to send the kernel-mode driver an IOCTL_AUX_GET_CAPABILITIES control code.
The user-mode driver fills the AUXCAPS structure.