This structure contains fields for the MCI_GROUP message.
typedef struct _MCI_GROUP_PARMS {
HWND hwndCallback; /* Window handle. */
USHORT usGroupID; /* Group ID returned. */
USHORT usReserved0; /* Reserved. */
ULONG ulStructLength; /* Length of structure. */
USHORT usMasterID; /* ID of master device. */
USHORT usReserved1; /* Reserved. */
PSZ pszGroupAlias; /* Alias name. */
ULONG ulNumDevices; /* Number of devices in group. */
PULONG paulDeviceID; /* Device IDs in the group. */
} MCI_GROUP_PARMS;
typedef MCI _ GROUP _ PARMS * PMCI _ GROUP _ PARMS ;