The local-time
library is a Common Lisp library for the manipulation of
dates, times and intervals. It was originally based almost entirely
upon Erik Naggum's paper The Long Painful History of Time
[NaggumPaper]. Many of the core concepts originated from this paper,
such as the seperation of days and seconds, the choice of 2000-03-01
as the standard epoch, and the timestring format.
Caveats: This implementation assumes that time zone information is stored in the tzfile format. The default timezone is loaded from /etc/localtime. On non-POSIX systems, this will certainly give different results than the system time handling.