DRV_QUERYDEVNODE function
The DRV_QUERYDEVNODE message queries for the devnode number assigned to the device by the Plug and Play manager.
Syntax
DWORD xxxMessage(
UINT uDeviceID,
UINT uMsg,
DWORD_PTR dwParam1,
DWORD_PTR dwParam2
);
Parameters
uDeviceID
Specifies the ID of the target device.uMsg
Caller sets this parameter to DRV_QUERYDEVNODE when it calls xxxMessage to process this device message.dwParam1
Pointer to a caller-allocated DWORD variable into which the function writes the devnode number. If no devnode is assigned to the device, the function sets this variable to zero.dwParam2
Unused. Set this parameter to zero.
Return value
The xxxMessage function returns MMSYSERR_NOERROR if the message is handled successfully. Otherwise, it returns an appropriate error code.
Remarks
In Windows 2000 and later, the message always returns MMSYSERR_NOTSUPPORTED. This message is valid only for the waveInMessage, waveOutMessage, midiInMessage, midiOutMessage, and mixerMessage 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.
Requirements
Target platform |
Desktop |
Version |
Supported in Microsoft Windows Me/98 and not supported Windows 2000 and later operating systems. |
Header |
Mmddk.h (include Mmddk.h) |