tm
Contains time information
struct tm { int tm_sec ; int tm_min ; int tm_hour ; int tm_mday ; int tm_mon ; int tm_year ; int tm_wday ; int tm_yday ; int tm_isdst ; };
The original values of the tm_sec, tm_min, tm_hour, tm_mday, and tm_mon fields are not restricted to ranges described for the tm structure. If these fields are not in their proper ranges, they are adjusted so that they are in the proper ranges. Values for the tm_wday and tm_yday fields are computed after all the other fields have been adjusted.
The value of the tm_isdst field depends upon whether you have linked your application to the PRELUDE.OBJ file or the NWPRE.OBJ file .
Some locales such Korean, Chinese, and Italian use the tm_wday structure field for the standard date format. If the tm_wday structure field is not set, an incorrect day will be displayed. An application which sets only the year, month, and day structure fields can compute the weekday by calling the C library function:
mktime(timePtr)