MM MCIPASSDEVICE

This message notifies an application that the use of a device is being gained or lost.

Syntax

MsgParam1
USHORT usDeviceID; /* Device ID. */
USHORT usReserved; /* Reserved. */

MsgParam2
USHORT usEvent;    /* Gaining or losing use of device. */
USHORT usReserved; /* Reserved. */

Parameters

usDeviceID (USHORT) - input

Device ID.

usReserved (USHORT) - input

Reserved.

usEvent (USHORT) - input

Indicates whether use of the device is being gained or lost:

• MCI_GAINING_USE The device is being gained.
• MCI_LOSING_USE The device is being lost.

usReserved (USHORT) - input

Reserved.

Returns

rc (BOOL) - return

Success indicator.

TRUE: Successful completion.

FALSE: Error occurred. (Note: The return value is typically ignored for this posted message.)

Remarks

The window handle specified in the hwndCallback field of the structure passed with the MCI_OPEN command is used as the window handle for the MM_MCIPASSDEVICE messages.

Default Processing

The default window procedure does not expect to receive this message and therefore takes no action on it, other than to set rc to the default value of FALSE.