anchor.diff:      tc_try(api_to_connect_tcp4,
              fun() ->
                      ?TT(?SECS(10)),
  -                   InitState = #{domain => inet, timeout => 5000},
  +                   InitState = #{domain        => inet,
  +                                 backlog       => 1,
  +                                 timeout       => 5000,
  +                                 connect_limit => 3},
                      ok = api_to_connect_tcp(InitState)
              end).
   
  
positive.code:                            _MRef = erlang:monitor(process, Server),
                             ok
                     end},
           #{desc => "which local address",
             cmd  => fun(#{domain := Domain} = State) ->
                             LAddr = which_local_addr(Domain),
                             LSA   = #{family => Domain, addr => LAddr},
                             {ok, State#{local_sa => LSA}}
                     end},
           #{desc => "create socket 1",
             cmd  => fun(#{domain := Domain} = State) ->
                             case socket:open(Domain, stream, tcp) of
                                 {ok, Sock} ->
                                     {ok, State#{sock1 => Sock}};
                                 {error, _} = ERROR ->
                                     ERROR
                             end
                     end},
           #{desc => "create socket 2",
             cmd  => fun(#{domain := Domain} = State) ->
                             case socket:open(Domain, stream, tcp) of
                                 {ok, Sock} ->
                                     {ok, State#{sock2 => Sock}};
                                 {error, _} = ERROR ->
                                     ERROR
                             end
                     end},
           #{desc => "create socket 3",
             cmd  => fun(#{domain := Domain} = State) ->
                             case socket:open(Domain, stream, tcp) of
                                 {ok, Sock} ->
                                     {ok, State#{sock3 => Sock}};
                                 {error, _} = ERROR ->
                                     ERROR
                             end
                     end},
           #{desc => "bind socket 1 to local address",
             cmd  => fun(#{sock1 := Sock, local_sa := LSA} = _State) ->
                             case socket:bind(Sock, LSA) of
                                 {ok, _} ->
                                     ok;
                                 {error, _} = ERROR ->
                                     ERROR
                             end
                     end},
           #{desc => "bind socket 2 to local address",
             cmd  => fun(#{sock2 := Sock, local_sa := LSA} = _State) ->
                             case socket:bind(Sock, LSA) of
                                 {ok, _} ->
                                     ok;
                                 {error, _} = ERROR ->
                                     ERROR
                             end
                     end},
           #{desc => "bind socket 3 to local address",
             cmd  => fun(#{sock3 := Sock, local_sa := LSA} = _State) ->
                             case socket:bind(Sock, LSA) of
                                 {ok, _} ->
                                     ok;
                                 {error, _} = ERROR ->
                                     ERROR
                             end
                     end},
  
           %% *** Synchronize with the server ***
           #{desc => "order server start",
             cmd  => fun(#{server := Server}) ->
                             ?SEV_ANNOUNCE_START(Server),
                             ok
                     end},
           #{desc => "await server ready (init)",
  
negative.code:                            end
                     end},
           #{desc => "make listen socket (with backlog = 1)",
             cmd  => fun(#{lsock := LSock, backlog := Backlog}) ->
                             socket:listen(LSock, Backlog)
                     end},
           #{desc => "announce ready (init)",
             cmd  => fun(#{tester := Tester, lport := Port}) ->
  