anchor.diff:  
            %% *** The init part ***
            #{desc => "which server (local) address",
  -           cmd  => fun(#{domain := Domain, server_port := Port} = State) ->
  -                           LAddr = which_local_addr(Domain),
  -                           LSA   = #{family => Domain, 
  -                                     addr   => LAddr},
  -                           SSA   = LSA#{port => Port},
  +           cmd  => fun(#{domain      := local = Domain,
  +                         server_path := Path} = State) ->
  +                           LSA = which_local_socket_addr(Domain),
  +                           SSA = #{family => Domain, path => Path},
  +                           {ok, State#{local_sa => LSA, server_sa => SSA}};
  +                      (#{domain := Domain, server_port := Port} = State) ->
  +                           LSA = which_local_socket_addr(Domain),
  +                           SSA = LSA#{port => Port},
                              {ok, State#{local_sa => LSA, server_sa => SSA}}
                      end},
            #{desc => "create socket",
  -           cmd  => fun(#{domain := Domain} = State) ->
  -                           case socket:open(Domain, stream, tcp) of
  +           cmd  => fun(#{domain := Domain,
  +                         type   := Type,
  +                         proto  := Proto} = State) ->
  +                           case socket:open(Domain, Type, Proto) of
                                  {ok, Sock} ->
                                      {ok, State#{sock => Sock}};
                                  {error, _} = ERROR ->
  
positive.code:                    end},
           #{desc => "which local address",
             cmd  => fun(#{domain := Domain} = State) ->
                             LAddr = which_local_addr(Domain),
                             LSA   = #{family => Domain, addr => LAddr},
                             {ok, State#{lsa => LSA}}
                     end},
           #{desc => "create (listen) socket",
  
negative.code: api_b_open_and_close_tcpL(_Config) when is_list(_Config) ->
      ?TT(?SECS(5)),
      tc_try(api_b_open_and_close_tcpL,
             fun() -> supports_unix_domain_socket() end,
             fun() ->
                     InitState = #{domain   => local,
                                   type     => stream,
  