#define _POSIX_C_SOURCE 200809L

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

int main() {

    struct timespec resolution;

    if ( clock_getres( CLOCK_REALTIME, &resolution ) == -1 ) {
        perror( "clock_getres" );
        return EXIT_FAILURE;
    }

    printf( "Resolution : %ld s et %ld ns\n",
            (long) resolution.tv_sec, resolution.tv_nsec );

    return EXIT_SUCCESS;
}