| MCI_NOTIFY | Specifies that MCI should post the MM_MCINOTIFY message when this command completes. The window that receives this message is specified in the dwCallback field of the data structure identified by lParam2. | |
| MCI_TEST | Queries the device to determine if it can execute the command. The device returns an error if it is incapable of executing the command. It returns no error if it can handle the command. MCI returns control to the application without executing the command. | |
| MCI_WAIT | Specifies that the play operation should finish before MCI returns control to the application. | |
| MCI_FROM | Specifies that a starting position is included in the dwFrom field of the data structure identified by lParam2. The starting position specifies the position to seek to before playing. The position value is specified in the current time format. The position used by the device is affected by whether seek exactly is enabled. If the starting position is omitted and playing is currently paused or the device is cued, then playing starts at the current position. If the starting position is omitted and playing is stopped, the resulting seek might change the position to a previous key-frame image. | |
| MCI_TO | Specifies that an ending position is included in the dwTo field of the data structure identified by lParam2. When the current time format is frames, the ending position specifies the number of the frame displayed when the motion video stops. If it is not specified, playing continues until the last valid position is reached. In either case, when playing is done, the workspace has an image displayed in the window. Most devices do not play the audio associated with the frame specified for the ending position. | |
| LPMCI_PLAY_PARMS lParam2 | Specifies a far pointer to an MCI_PLAY_PARMS data structure. (Digital-video devices can use this data structure rather than their device-specific data structure if the extended data fields are not being used.) | |