decode-universal-time - ANSI Common Lisp

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decode-universal-time (Function)

Syntax:

— Function: decode-universal-time universal-time &optional time-zone → second, minute, hour, date, month, year, day, daylight-p, zone

Arguments and Values:

universal-time—a universal time.

time-zone—a time zone.

second, minute, hour, date, month, year, day, daylight-p, zone—a decoded time.

Description:

Returns the decoded time represented by the given universal time.

If time-zone is not supplied, it defaults to the current time zone adjusted for daylight saving time. If time-zone is supplied, daylight saving time information is ignored. The daylight saving time flag is nil if time-zone is supplied.

Examples:

 (decode-universal-time 0 0) → 0, 0, 0, 1, 1, 1900, 0, false, 0

;; The next two examples assume Eastern Daylight Time.
 (decode-universal-time 2414296800 5) → 0, 0, 1, 4, 7, 1976, 6, false, 5
 (decode-universal-time 2414293200) → 0, 0, 1, 4, 7, 1976, 6, true, 5

;; This example assumes that the time zone is Eastern Daylight Time
;; (and that the time zone is constant throughout the example).
 (let* ((here (nth 8 (multiple-value-list (get-decoded-time)))) ;Time zone
        (recently (get-universal-time))
        (a (nthcdr 7 (multiple-value-list (decode-universal-time recently))))
        (b (nthcdr 7 (multiple-value-list (decode-universal-time recently here)))))
   (list a b (equal a b))) → ((T 5) (NIL 5) NIL)

Affected By:

Implementation-dependent mechanisms for calculating when or if daylight savings time is in effect for any given session.