XPLMLoadDataFile

XPLM_API int        XPLMLoadDataFile(
                         XPLMDataFileType     inFileType,
                         const char *         inFilePath);    /* Can be NULL */

Loads a data file of a given type. Paths must be relative to the X-System folder. To clear the replay, pass a NULL file name (this is only valid with replay movies, not sit files).