
  TYPE

    nlt$sl_machine_state = (nlc$sl_closed, nlc$sl_connect_confirm_wait,
      nlc$sl_call_wait, nlc$sl_call_ok_wait, nlc$sl_call_response_wait,
      nlc$sl_data_transfer, nlc$sl_m_r_fr_wait, nlc$sl_fwd_mark_wait,
      nlc$sl_synch_response_wait, nlc$sl_rev_mark_wait,
      nlc$sl_synch_collision_fr, nlc$sl_disconnect_wait);
