#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>

int main() {
  struct timeval *tv = malloc(sizeof(struct timeval));
  struct timezone *tz = malloc(sizeof(struct timezone));
  for (int i = 0; i < 15; i++) {
    gettimeofday(tv, NULL);
    printf("%ld.%06ld\n", tv->tv_sec, tv->tv_usec);
    for (int i = 0; i < 10; i++) {
      usleep(500000);
    }
  }
  gettimeofday(tv, NULL);
  printf("tv = %ld.%06ld\n", tv->tv_sec, tv->tv_usec);
  // printf("tz_minuteswest = %d,tz_dsttime = %d", (*tz).tz_minuteswest,
  // (*tz).tz_dsttime);
  return 0;
}