PL/I PL/1 Year 2000 built-in functions

The Year 2000 built-in functions implemented in IBM's workstation PL/I compilers -- OS/2, AIX, Windows NT (some also in Windows 95) -- are outlined in the following list. Note that these functions (where appropriate) can also handle 2-digit years with 100-year windowing, if required, as part of IBM's Millennium Language Extensions for those same compilers.

These date functions will work on dates on or after 15th October 1582 (that is, a little after the date when Christopher Columbus is credited with discovering America).

• DATETIME, which returns the date in one of 37 different formats. The date comes in various flavors: year first, month first, or day first.
  The month comes as a numeric value, or in three-letter form like May or MAY.
  The year comes as 4-digit year or a 2-digit year.
  Your choice of format is determined from a template argument: e.g. YYYYMmmDD will give 1998Nov04 for the 4th November 1998.
• DAYS will give the number of days corresponding to a date given in one of the standard formats.
• DAYSTODATE converts a number of days (measured from the beginning of time 15 October 1582) into a date in one of the standard formats.
• DAYSTOSECS converts the given number of days into seconds.
• REPATTERN converts the given date (in one of the standard formats) into one of the other standard formats. In particular, it can be used for converting a date in a two-digit year format into a 4-digit year format and vice versa, for example.
• SECS converts a date into seconds.
• SECSTODATE converts a number of seconds into a date.
• SECSTODAYS converts a number of seconds into days.
• VALIDDATE checks whether a given date matches one of the standard date formats.
• WEEKDAY returns the day of the week corresponding to the given date (returns an integer representing the day number).
• Y4DATE converts a date having a 2-digit year into a 4-digit year.
• Y4JULIAN converts a date having a two-digit year format (YYDDD) into a 4-digit year format (YYYYDDD).
• Y4YEAR converts a two-digit year into a 4-digit year.

Updated 25th December 1999.