difftime (3)

NAME

       difftime - calculate time difference

SYNOPSIS

       #include <time.h>

       double difftime(time_t time1, time_t time0);

DESCRIPTION

       The  difftime()  function returns the number of seconds elapsed between
       time time1 and time time0, represented as a double.  The two times  are
       specified in calendar time, which represents the time elapsed since the
       Epoch (00:00:00 on January 1, 1970, Coordinated Universal Time  (UTC)).

CONFORMING TO

       SVID 3, BSD 4.3, ISO 9899

NOTES

       This  function  is required by ANSI C.  On a POSIX system, time_t is an
       arithmetic type, and one could just define
              #define difftime(t1,t0) (double)(t1 - t0)
       when the possible overflow in the subtraction is not a concern.

SEE ALSO

       date(1), gettimeofday(2), time(2), ctime(3), gmtime(3), localtime(3)

GNU                               1993-07-02                       difftime(3)