MMDRV_MESSAGE_PARAMS

This structure is passed to the WAV_IOControl function.

Syntax

typedef struct {
UINT uDeviceId;
UINT uMsg;
DWORD dwUser;
DWORD dwParam1;
DWORD dwParam2;
} MMDRV_MESSAGE_PARAMS;

Members

uDeviceId

Device identifier—0, 1, 2, and so on—for the target device.

uMsg

One of the Wave Input Driver messages (WIDM_*) or Wave Output Driver messages (WODM_*).

dwUser

Specifies a device instance identifier. For the WODM_OPEN and WIDM_OPEN messages, this is an output member. The device creates an instance identifier and returns it in the address specified as the argument. For all other messages, this is an input member. This member is the instance identifier.

dwParam1

Specifies the first message member. Dependent on message type.

dwParam2

Specifies the second message member. Dependent on message type.

Remarks

The MMDRV_MESSAGE_PARAMS structure is declared in the Wavedev.h file.