Windows Multimedia DDK (mddkqh.hlp) (Table of Contents; Topic list)
wodMessage
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wodMessage
 
        DWORD wodMessage(uDeviceID, uMsg, dwUser, dwParam1, dwParam2)
 
        This user-supplied function is the entry point for a waveform
        output device driver.
 
Parameters
        UINT uDeviceID
            Specifies the ID of the target device.
 
        UINT uMsg
            Specifies the message being sent to the driver.
 
        DWORD dwUser
            For the WODM_OPEN message, the driver should fill this
            location with its instance data. For any other messages, the
            instance data is returned to the driver. Drivers supporting
            multiple clients can use this instance data to keep track of
            which client is associated with the message.
 
        DWORD dwParam1
            Specifies a message-dependent parameter.
 
        DWORD dwParam2
            Specifies a message-dependent parameter.
 
Return value
        Unless specified otherwise under a specific message, the driver
        should return an MMSYSERR_ or WAVERR_ error code.
 
Comments
        The driver should return MMSYSERR_NOTSUPPORTED if it does not
        support the specified message.
 
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