difftime(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ATTRIBUTES | STANDARDS | HISTORY | NOTES | SEE ALSO

difftime(3)             Library Functions Manual             difftime(3)

NAME         top

       difftime - calculate time difference

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <time.h>

       double difftime(time_t time1, time_t time0);

DESCRIPTION         top

       The difftime() function returns the number of seconds elapsed
       between time time1 and time time0, represented as a double.  Each
       of the times is specified in calendar time, which means its value
       is a measurement (in seconds) relative to the Epoch, 1970-01-01
       00:00:00 +0000 (UTC).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌─────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                           Attribute     Value   │
       ├─────────────────────────────────────┼───────────────┼─────────┤
       │ difftime()                          │ Thread safety │ MT-Safe │
       └─────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       POSIX.1-2001, C89, SVr4, 4.3BSD.

NOTES         top

       On a POSIX system, time_t is an arithmetic type, and one could
       just define

           #define my_difftime(t1,t0) (double)(t1 - t0)

       when the possible overflow in the subtraction is not a concern.

SEE ALSO         top

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

Linux man-pages (unreleased)     (date)                      difftime(3)

Pages that refer to this page: ctime(3)time_t(3type)