The Ruby Way: Solutions and Techniques in Ruby Programming, Second Edition

7.2. Working with Specific Times (Post-epoch)

Most software only needs to work with dates in the future or in the recent past. For these circumstances, the Time class is adequate. The relevant class methods are mktime, local, gm, and utc.

The mktime method creates a new Time object based on the parameters passed to it. These time units are given in reverse from longest to shortest: year, month, day, hours, minutes, seconds, microseconds. All but the year are optional; they default to the lowest possible value. The microseconds may be ignored on many architectures. The hours must be between 0 and 23 (that is, a 24-hour clock).

t1 = Time.mktime(2001) # January 1, 2001 at 0:00:00 t2 = Time.mktime(2001,3) t3 = Time.mktime(2001,3,15) t4 = Time.mktime(2001,3,15,21) ...