NAME | SYNOPSIS | DESCRIPTION | CONFORMING TO | NOTES | SEE ALSO | COLOPHON
DIFFTIME(3) Linux Programmer's Manual DIFFTIME(3)
difftime - calculate time difference
#include <time.h>
double difftime(time_t time1, time_t time0);
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)).
SVr4, 4.3BSD, C89, C99.
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. On other
systems, the data type time_t might use some other encoding where subtraction
doesn't work directly.
date(1), gettimeofday(2), time(2), ctime(3), gmtime(3), localtime(3)
This page is part of release 3.23 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
GNU 2002-02-28 DIFFTIME(3)