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

struct timespec ts = {.tv_nsec = 30, .tv_sec = 0};
volatile int dummy = 0;

int main(void) {
    struct timespec start, end;

    clock_gettime(CLOCK_MONOTONIC, &start);

    for (int a = 0; a < 10000; a++) {
        // Keep in mind that yield is a syscall, it does not sleep, but places
        // the process at the end of the run queue and gives other threads a
        // chance to run.
        sched_yield();
        dummy++; // Do some stuff to the dummy to avoid optimizations

        nanosleep(&ts, NULL);

        printf("Iteration %d\n", a);
        fflush(stdout);
    }

    clock_gettime(CLOCK_MONOTONIC, &end);

    long sec = end.tv_sec - start.tv_sec;
    long nanos = end.tv_nsec - start.tv_nsec;

    double elapsed = sec + nanos * 1e-9;

    printf("Elapsed time: %.2fs\n", elapsed);

    return 0;
}