int signal_generator_read(struct node *n, struct sample *smps[],
                          unsigned cnt, unsigned *release)
{
  struct signal_generator *s = (struct signal_generator *) n->_vd;
  struct timespace ts;
  int steps;

  /* Block until 1/p->rate seconds elapsed */
  steps = task_wait(&s->task);

  if (steps > 1 && s->monitor_missed) {
    warn("Missed steps: %u", steps-1);

    s->missed_steps += steps-1;
  }
  
  ts = time_now();

  /**
   * Generate sample(s) with signal and timestamp ts .
   * Return this sample via the *smps[] parameter of
   * signal_generator_read()
   */
}