MMProgRef - MCI Command Messages

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Multimedia Programming Reference

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This section describes the media control interface command messages.

All messages except system messages operate in an asynchronous mode without notification unless **MCI_NOTIFY** or **MCI_WAIT** is specified. These two flags are mutually exclusive. If both are used, the error **MCIERR_FLAGS_NOT_COMPATIBLE** is returned.

If **MCI_WAIT** is used, control is not returned to the caller until the command completes. **MCI_NOTIFY** returns control to the caller and then completes the command. A notification will be sent to the application if **MCIERR_SUCCESS** was returned on the call. The second parameter specified for each message is a pointer to a control block structure associated with that message. This pointer is passed in the *pParam2* parameter of mciSendCommand. The following table lists the command messages:

Command	Description
MCI_ACQUIREDEVICE	Requests the use of the media device.
MCI_BUFFER	Allows an application to allocate (or deallocate) buffers for use with the audio device.
MCI_CAPTURE	Causes a video device to capture the current video image.
MCI_CLOSE	Closes a device.
MCI_CONNECTION	Queries the device ID of a connected device.
MCI_CONNECTOR	Enables or disables a connector, or to query the status of a connector.
MCI_CONNECTORINFO	Determines the total number of connectors on a device, the number of connectors of a specific type, the type of each of the connectors, and whether or not a particular type of connection is valid for a connector.
MCI_COPY	Copies data from the device element to the clipboard or a user-supplied buffer.
MCI_CUE	Signals a device to ready itself (preroll) so that a subsequent playback or recording operation begins with minimum delay.
MCI_CUT	Removes data from the device element and copies it to the clipboard or a user-supplied buffer.
MCI_DEFAULT_CONNECTION	Makes, breaks, and queries default connections between devices.
MCI_DELETE	Removes the specified range of data from the device element.
MCI_DEVICESETTINGS	Allows a media control driver (MCD) to insert custom settings pages into a Settings notebook.
MCI_ESCAPE	Sends a string directly to the driver.
MCI_FREEZE	Freezes the motion of a video image.
MCI_GETDEVCAPS	Returns static information about a particular driver.
MCI_GETIMAGEBUFFER	Reads data from the image capture buffer.
MCI_GETIMAGEPALETTE	Obtains a palette or color map for the current image.
MCI_GETTOC	Interrogates the device, and returns a table of contents structure for the currently loaded disk. (CD Audio Only)
MCI_GROUP	Used to provide the appropriate message handling for GROUP commands. GROUP commands allow you to control several multimedia devices from a single MCI command.
MCI_INFO	Returns string information from a media device.
MCI_LOAD	Specifies a new file or RIFF chunk to be loaded into an already existing device context.
MCI_MASTERAUDIO	Provides support for setting and retrieving system-wide audio control parameters.
MCI_MIXNOTIFY	Notifies an application of mixer attribute changes.
MCI_MIXSETUP	Informs the mixer device that the application wishes to read or write buffers directly and sets up the device in the correct mode.
MCI_OPEN	Opens a logical multimedia device and creates a new device context for use by an application.
MCI_PASTE	Pastes data from the clipboard or a user-supplied buffer into the specified range of a device element.
MCI_PAUSE	Suspends playback or recording.
MCI_PLAY	Signals the device to begin transmitting data.
MCI_PUT	Sets the source and destination rectangle arrays for the transformation of the video image.
MCI_RECORD	Starts the device recording input data.
MCI_REDO	Redoes the record, cut, paste, or delete operation most recently undone by MCI_UNDO.
MCI_RELEASEDEVICE	Releases the exclusive use of physical device resources by a device context or device group.
MCI_RESTORE	Causes a video device to restore the image or bitmap.
MCI_RESUME	Resumes playing or recording from a paused state.
MCI_REWIND	Seeks the media to the beginning point.
MCI_SAVE	This message saves the current file.
MCI_SEEK	Changes the current media position of the device.
MCI_SET	Sets device information.
MCI_SET_CUEPOINT	Sets run-time cue points in the media device.
MCI_SETIMAGEBUFFER	Writes data to the image capture buffer.
MCI_SETIMAGEPALETTE	Sets a palette or color map to be used for mapping images.
MCI_SET_POSITION_ADVISE	Enables periodic position-change messages from the media device.
MCI_SET_SYNC_OFFSET	Specifies positional offsets for devices operating in synchronization.
MCI_SETTUNER	Sets the frequency for the tuner device.
MCI_SPIN	Spins the player up or down.
MCI_STATUS	Obtains information about the status of a media control interface device.
MCI_STEP	Steps the player one or more frames.
MCI_STOP	Stops audio or video playback or recording.
MCI_SYSINFO	Returns information about media control interface devices.
MCI_UNDO	Undoes the operation most recently performed by record, cut, paste, or delete.
MCI_UNFREEZE	Restores motion to an area of the display frozen with MCI_FREEZE.
MCI_WHERE	Returns the extent of the clipping rectangles.
MCI_WINDOW	Specifies the window and the window characteristics that a graphic device should use for display.