universal-time—a universal time.
second, minute, hour, date, month, year, day, daylight-p, zone—a decoded time.
get-universal-time returns the current time, represented as a universal time.
get-decoded-time returns the current time, represented as a decoded time.
;; At noon on July 4, 1976 in Eastern Daylight Time. (get-decoded-time) → 0, 0, 12, 4, 7, 1976, 6, true, 5 ;; At exactly the same instant. (get-universal-time) → 2414332800 ;; Exactly five minutes later. (get-universal-time) → 2414333100 ;; The difference is 300 seconds (five minutes) (- * **) → 300
The time of day (i.e., the passage of time), the system clock's ability to keep accurate time, and the accuracy of the system clock's initial setting.
An error of type
error might be signaled if the current time cannot be determined.
decode-universal-time, encode-universal-time, Section 25.1.4 (Time)
(get-decoded-time) ≡ (decode-universal-time (get-universal-time))
No implementation is required to have a way to verify that the
time returned is correct. However, if an implementation provides
a validity check (e.g., the failure to have properly initialized the system
clock can be reliably detected) and that validity check fails,
the implementation is strongly encouraged (but not required)
to signal an error of type
error (rather than, for example, returning a
known-to-be-wrong value) that is correctable by allowing the user
to interactively set the correct time.