listing kafka groups

rk_groups.c

  const struct rd_kafka_group_list *grplist;                                                                          
  err = rd_kafka_list_groups(rk, NULL, &grplist, 5000);                                                               
  assert (!err);                                                                                                      
  for (i = 0 ; i < grplist->group_cnt ; i++) {                                                                        
    const struct rd_kafka_group_info *gi = &grplist->groups[i];                                                       
    printf("%s\n", gi->group);                                                                                        
  }                                                                                                                   
  rd_kafka_group_list_destroy(grplist);