anchor.diff:      ?TT(?SECS(10)),
       tc_try(api_a_connect_tcp4,
              fun() ->
  -                   Connect = fun(Sock, SockAddr) ->
  -                                     socket:connect(Sock, SockAddr, nowait)
  -                             end,
  -                   Send = fun(Sock, Data) ->
  -                                  socket:send(Sock, Data)
  -                          end,
  -                   Recv = fun(Sock) ->
  -                                  socket:recv(Sock)
  -                          end,
  -                   InitState = #{domain  => inet,
  -                                 connect => Connect,
  -                                 send    => Send,
  -                                 recv    => Recv},
  -                   ok = api_a_connect_tcp(InitState)
  +                   ok = api_a_connect_tcpD(inet)
              end).
  +
  +
  +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  +
  +%% Basically establish a TCP connection via an async connect. IPv6.
  +
  +api_a_connect_tcp6(suite) ->
  +    [];
  +api_a_connect_tcp6(doc) ->
  +    [];
  +api_a_connect_tcp6(_Config) when is_list(_Config) ->
  +    ?TT(?SECS(10)),
  +    tc_try(api_a_connect_tcp6,
  +           fun() -> has_support_ipv6() end,
  +           fun() ->
  +                   ok = api_a_connect_tcpD(inet6)
  +           end).
  +
  +
  +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  +
  +api_a_connect_tcpD(Domain) ->
  +    Connect = fun(Sock, SockAddr) ->
  +                      socket:connect(Sock, SockAddr, nowait)
  +              end,
  +    Send = fun(Sock, Data) ->
  +                   socket:send(Sock, Data)
  +           end,
  +    Recv = fun(Sock) ->
  +                   socket:recv(Sock)
  +           end,
  +    InitState = #{domain  => Domain,
  +                  connect => Connect,
  +                  send    => Send,
  +                  recv    => Recv},
  +    api_a_connect_tcp(InitState).
   
   
   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
positive.code: api_async_cases() ->
      [
       api_a_connect_tcp4,
       api_a_sendto_and_recvfrom_udp4,
       api_a_sendmsg_and_recvmsg_udp4,
       api_a_send_and_recv_tcp4,
  
negative.code: 
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  %% Basically establish a TCP connection via an async connect. IPv4.
  
  api_a_connect_tcp4(suite) ->
      [];
  