#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

int main(const int argc, const char *argv[]) {
    if (argc != 2) {
        fprintf(stderr, "usage: main <cycles>\n");
        return 1;
    }

    const long cycles = strtol(argv[1], NULL, 10);

    struct timespec start, end;
    clock_gettime(CLOCK_MONOTONIC, &start);

    int pipes[2];
    for (int i = 0; i < cycles; i++) {
        if (pipe(pipes) != 0) {
            fprintf(stderr, "unable to create pipes: %s\n", strerror(errno));
            exit(1);
        }
        close(pipes[0]);
        close(pipes[1]);
    }

    clock_gettime(CLOCK_MONOTONIC, &end);
    const long duration = end.tv_sec * 1000000000 + end.tv_nsec - start.tv_sec * 1000000000 - start.tv_nsec;
    printf("start: %li.%09li\nend:   %li.%09li\nduration: %li,%03li,%03li ns\n", start.tv_sec, start.tv_nsec, end.tv_sec, end.tv_nsec, duration / 1000000, duration / 1000 % 1000, duration % 1000);
}