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. 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

For an explanation of the terms used in this section, see attributes(7).
Interface Attribute Value
difftime () Thread safety MT-Safe

CONFORMING TO

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

NOTES

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)

Information

Source
Linux kernel
OS/version
GNU
Source updated
August 8, 2015
Page created
February 9, 2018
Page generated
December 2, 2018