difftime(3) — Linux manual page

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
       time is a count of seconds.

       difftime(b, a) acts like (b-a) except that the result does not
       overflow and is rounded to double.

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.

SEE ALSO         top

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

COLOPHON         top

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Linux man-pages 6.15            2025-05-17                    difftime(3)

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

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