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(librep.info)Timestamps

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Timestamps
----------

   As in UNIX, `librep' measures time as the number of seconds since
January 1st, 1970 (known as the "epoch"). For historical reasons rep
stores timestamps as a pair of integers, using a cons cell.

   The first integer records the number of whole days since the epoch,
the second records the number of seconds since the start of the day (in
universal time).

   These function are exported by the `rep.system' module:

 - Function: current-time
     Return the number of seconds since the epoch, in a cons-cell.

          (current-time)
              => (10744 . 61063)

 - Function: fix-time timestamp
     Ensure that the two parts of TIMESTAMP (a pair or integers) are
     consistent, simply that the number of seconds is less than the
     number of seconds in a whole day. If not, the timestamp is
     adjusted to meet this constraint.

 - Function: time-later-p timestamp-1 timestamp-2
     Returns true if TIMESTAMP-1 is later than TIMESTAMP-2.

   On the plus side, this scheme won't wrap around as quickly as UNIX's
`time_t' will ;-)

   The `rep.util.time' module also provides some functions for
manipulating timestamps:

 - Function: time->seconds timestamp
     Convert TIMESTAMP to an integer, the number of seconds since the
     epoch that it represents.

 - Function: seconds->time seconds
     Convert from an integer SECONDS to a timestamp object.

 - Function: time- timestamp-1 timestamp-2
     Return the number of seconds difference between TIMESTAMP-1 and
     TIMESTAMP-2.

 - Constant: seconds-per-day
     The number of seconds in a 24-hour day.