typedef struct {
    DWORD  dwCallback;
    DWORD  lpfilename;
} MCI_SAVE_PARMS;
 The MCI_SAVE_PARMS structure contains the information for MCI_SAVE message. When assigning data to the members in this structure, set the corresponding MCI flags in the lParam1 parameter of mciSendCommand to validate the members.
MCI_SAVE