DIFFTIME

Section: Linux Programmer's Manual (3)
Updated: 2015-08-08
Index Return to Main Contents

---

 

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)  

COLOPHON

This page is part of release 4.13 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/.

---

 

Index

NAME

SYNOPSIS

DESCRIPTION

ATTRIBUTES

CONFORMING TO

NOTES

SEE ALSO

COLOPHON