Real Time and Date

(current-seconds) returns the current time in seconds. This time is always an exact integer based on a platform-specific starting date (with an architecture-specific minimum and maximum value).

The value of (current-seconds) increases as time passes, so the values returned by current-seconds can be compared directly with the numerical comparison procedures. The current time in seconds can also be compared with a time returned by file-modify-seconds (see section 11.2.2).

(seconds->date secs) takes secs, a platform-specific time in seconds returned by current-seconds or file-modify-seconds, and returns an instance of the date structure type with the following fields:

• second : 0 to 61 (60 and 61 are for unusual leap-seconds)
• minute : 0 to 59
• hour : 0 to 23
• day : 1 to 31
• month : 1 to 12
• year : e.g., 1996
• week-day : 0 (Sunday) to 6 (Saturday)
• year-day : 0 to 365 (364 in non-leap years)
• dst? : #t (daylight savings time) or #f

The value returned by current-seconds or file-modify-seconds is not portable among platforms. Convert a time in seconds using seconds->date when portability is needed.

See also section 15.2.7 for additional date utilities.