NAME | SYNOPSIS | DESCRIPTION | ATTRIBUTES | CONFORMING TO | NOTES | SEE ALSO | COLOPHON

DIFFTIME(3)               Linux Programmer's Manual              DIFFTIME(3)

NAME         top

       difftime - calculate time difference

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 │
       └───────────┴───────────────┴─────────┘

CONFORMING TO         top

       POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.

NOTES         top

       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         top

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

COLOPHON         top

       This page is part of release 4.08 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.

GNU                              2015-08-08                      DIFFTIME(3)