+stamp_t get_stamp(date_t *date);
+int get_mins(date_t *start, date_t *end);
+int compare(date_t *a, date_t *b);
+int before(date_t *start, int year, int month, int day, int hour, int min);
+
+int all_day(date_t *start, date_t *end);
+int no_date(date_t *date);
+