static void mergeTables(struct receiver **primary, struct receiver **secondary) {
  struct receiver *r, *s, *tmp;

  HASH_ITER(hh, *primary, r, tmp) {
    HASH_FIND_INT(*secondary, (int *)&(r->addr), s);
    if(s == NULL){
      s = (struct receiver *)malloc(sizeof(struct receiver));
      if(!s) return;

      s->addr = r->addr;
      s->version = r->version;
      s->num_pkts = r->num_pkts;

      HASH_ADD_INT(*secondary, addr, s);
    }
    else
      s->num_pkts += r->num_pkts;

    HASH_DEL(*primary, r);
    free(r);
  }
}
static void mergeTables(struct receiver **primary, struct receiver **secondary) {
  struct receiver *r, *s, *tmp;

  HASH_ITER(hh, *primary, r, tmp) {
    HASH_FIND_INT(*secondary, (int *)&(r->addr), s);
    if(s == NULL){
      s = (struct receiver *)malloc(sizeof(struct receiver));
      if(!s) return;

      s->addr = r->addr;
      s->version = r->version;
      s->num_pkts = r->num_pkts;

      HASH_ADD_INT(*secondary, addr, s);
    }
    else
      s->num_pkts += r->num_pkts;

    HASH_DEL(*primary, r);
    free(r);
  }
}