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WAVEOPENDESC
 
        This structure contains information needed by a waveform input
        or waveform output device driver when devices are opened with a
        WODM_OPEN or WIDM_OPEN message.
 
        typedef struct waveopendesc_tag {
            HANDLE hWave;
            LPWAVEFORMAT lpFormat;
            DWORD dwCallback;
            DWORD dwInstance;
        } WAVEOPENDESC;
 
Fields
        HANDLE hWave
            Specifies the client's handle to the device, assigned by
            MMSYSTEM. Use this handle when notifying the client with
            the DriverCallback function.
 
        LPWAVEFORMAT lpFormat
            Specifies a far pointer to a WAVEFORMAT structure,
            indicating the waveform data format requested by the
            client.
 
        DWORD dwCallback
            Specifies either the address of a callback function, a
            window handle, or a task handle, depending on the flags
            specified in the dwParam2 parameter of the WODM_OPEN or
            WIDM_OPEN message. If this field contains a handle it is
            contained in the low-order word. The driver uses this
            information to notify the client using the DriverCallback
            function.
 
        DWORD dwInstance
            Specifies a DWORD of instance information for the client.
            This instance information is returned to the client whenever
            the driver notifies the client using the DriverCallback
            function.
 
Comments
    Drivers can support other formats in addition to those specified in
    the dwFormats field.
 
 
See also
        WODM_OPEN, WIDM_OPEN
 
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