difftime()

Calculate the difference between two times

Synopsis:

#include <time.h>

double difftime( time_t time1, 
                 time_t time0 );

Arguments:

time1, time0

The times to compare, expressed as time_t objects.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The difftime() function calculates the difference between the calendar times specified by time1 and time0:

time1 - time0

Returns:

The difference between the two times (in seconds).

Examples:

#include <stdio.h>
#include <time.h>
#include <stdlib.h>

void compute( void )
{
    int i, j;

    for( i = 1; i <= 20; i++ ) {
        for( j = 1; j <= 20; j++ ) {
            printf( "%3d ", i * j );
        }
        printf( "\n" );
    }
}

int main( void )
{
    time_t start_time, end_time;

    start_time = time( NULL );
    compute();
    end_time = time( NULL );
    printf( "Elapsed time: %f seconds\n",
        difftime( end_time, start_time ) );

    return EXIT_SUCCESS;
}

Classification:

ANSI, POSIX 1003.1

See also:

asctime(), clock(), ctime(), gmtime(), localtime(), mktime(), strftime(), time(), tzset()