MCI_STOP

This message is sent to stop playback or recording. For video recording, issuing this message stops the process regardless of whether a "TO" position has been reached.

Syntax

param1
ULONG ulParam1; /* Message flags. */

param2
PMCI_GENERIC_PARMS pParam2; /* Pointer to generic structure. */

Parameters

ulParam1 (ULONG) - input

This parameter can contain any of the following flags:

* MCI_NOTIFY — Posts a notification message to the window specified in the `hwndCallback` field of the structure pointed to by `pParam2` when the action completes or an error occurs.

* MCI_WAIT — Does not return control until the action is completed or an error occurs.

pParam2 (PMCI_GENERIC_PARMS) - input

A pointer to the default media control interface (MCI_GENERIC_PARMS) data structure.

Return Value

rc (ULONG)

Return codes indicating success or type of failure:

* MCIERR_SUCCESS — 0 is returned if the function succeeds.

* MCIERR_INVALID_DEVICE_ID — The device ID is not valid.

* MCIERR_INSTANCE_INACTIVE — The device ID is currently inactive. Issue MCI_ACQUIREDEVICE to make the device ID active.

* MCIERR_MISSING_FLAG — A required flag is missing.

* MCIERR_UNSUPPORTED_FLAG — The given flag is unsupported for this device.

* MCIERR_INVALID_CALLBACK_HANDLE — The given callback handle is invalid.

* MCIERR_HARDWARE — Device hardware error.

* MCIERR_UNSUPPORTED_FUNCTION — Unsupported function.

* MCIERR_INVALID_FLAG — Flag (`ulParam1`) is invalid.

* MCIERR_FLAGS_NOT_COMPATIBLE — Flags cannot be used together.

* MCIERR_INVALID_ITEM_FLAG — Invalid status item flag given.

* MCIERR_MISSING_ITEM — Missing status item flag.

* MCIERR_MISSING_PARAMETER — Required parameter is missing.

Remarks

• **Recording:** Once video recording is stopped, it cannot be restarted without overwriting the previous recording.
• **Latency:** If you intend to restart playback or recording with minimal latency, use MCI_PAUSE instead of MCI_STOP.

Related Messages

• MCI_PLAY
• MCI_RECORD

Example Code

The following code illustrates how to stop an audio or video device during playback or recording and receive notification upon completion.

   USHORT            usDeviceID;
   HWND              hwndMyWindow;
   MCI_GENERIC_PARMS mciGenericParms;    /* Info data structure for command */

   /* Assign hwndCallback the handle to the PM Window */
   mciGenericParms.hwndCallback = hwndMyWindow;

   /* Stop the device */
   mciSendCommand( usDeviceID,                /* Device ID               */
                   MCI_STOP,                  /* MCI stop message        */
                   MCI_NOTIFY,                /* Flag for this message   */
                   (PVOID) &mciGenericParms,  /* Data structure          */
                   0);                        /* No user parm            */