Clock_nanosleep does not return -1 / set errno EINTR - LINUX

I am new to Linux. I am trying to perform a simple task using clock_nanosleep. The problem is that clock_nanosleep does not set errno to EINTR after the signal is interrupted. I tried to clear the SA_RESTART flag. But no success. Here is my code. Thank.

void signalHandler( int signum )
{
    printf("Interrupt signal received.\n");
}

void *periodic_thread (void *param)
{
struct itimerspec its;
struct sigevent sig;
struct timespec next, period;
sigset_t blocked;

siginfo_t si;
timer_t mytimer;
int i, j;

/* create a timer that will be used to periodically send a signal */
sig.sigev_notify = SIGEV_SIGNAL;
sig.sigev_signo = SIGUSR1;
sig.sigev_value.sival_ptr = &sig;

timer_create(CLOCK_REALTIME, &sig, &mytimer);

struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = &signalHandler;
sigaction(SIGUSR1, &sa, NULL);

/* set the periodic timer */
its.it_value.tv_sec = 8;
its.it_value.tv_nsec = 00000000; 
its.it_interval.tv_sec = 0;
its.it_interval.tv_nsec = 0; ;
period.tv_sec = 5;
period.tv_nsec = 00000000; 

timer_settime(mytimer, 0, &its, NULL); 

printf("periodic thread started...\n");

j=1;

i = clock_gettime(CLOCK_MONOTONIC, &next);
while(1)
{
  next.tv_sec = next.tv_sec + period.tv_sec;
  next.tv_nsec = next.tv_nsec + period.tv_nsec;
  i = clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &next, 0);  
  printf("I am done \n");
  if((i == -1) && (errno == EINTR))
  break;
}

printf("...periodic thread end!\n");

timer_delete(mytimer);
return NULL;
}

int main()
{

  pthread_t mythread;
  pthread_attr_t myattr;

  //struct sched_param myparam;
  void *returnvalue;
  sigset_t blocked;


  /* initializes the thread attribute */
  pthread_attr_init(&myattr);


  printf("starting a periodic thread...\n");

  pthread_create(&mythread, &myattr, periodic_thread, NULL);

  pthread_attr_destroy(&myattr);

  /* wait the end of the thread we just created */
  pthread_join(mythread, &returnvalue);

  printf("ending main...\n");

return 0;
}

Exit →

  starting a periodic thread...
  periodic thread started...
  I am done 
  Interrupt signal received.
  I am done 
  I am done
  continues.. (Does not break the while(1))