The following code illustrates how to specify positional offsets for operating synchronized devices.
/* Set the sync offset for the device to 10 secs */
USHORT usDeviceID;
MCI_SYNC_OFFSET_PARMS msoparms;
msoparms.ulOffset = (ULONG) 10000; /* Current time format = MS */
mciSendCommand( usDeviceID, /* Device ID */
MCI_SET_SYNC_OFFSET, /* MCI set sync offset message */
MCI_WAIT, /* Flag for this message */
(PVOID) &msoparms, /* Data structure */
0); /* No user parm */