+/** \brief metafile area statistics
+ \param ma metafile area handle
+ \param no area number (0=first, 1=second, ..)
+ \param directory holds directory upon completion (if non-NULL)
+ \param used_bytes holds used bytes upon completion (if non-NULL)
+ \param max_bytes holds max size bytes upon completion (if non-NULL)
+ \retval 0 area number does not exist
+ \retval 1 area number exists (and directory,used_bytes,.. are set)
+*/
+int mf_area_directory_stat(MFile_area ma, int no, const char **directory,
+ double *used_bytes, double *max_bytes)