NAME
difftime - calculate time difference
SYNOPSIS
#include <time.h>
I double difftime(time_t time1 , time_t time0 );
DESCRIPTION
The
R 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)).
CONFORMING TO
SVr4, 4.3BSD, C89, C99
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.
On other systems, the data type
time_t
might use some other encoding
where subtraction doesn't work directly.
SEE ALSO
ČLÁNKY DO MAILU