anchor.diff:  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   
   %% Basically send and receive using the msg functions (sendmsg and recvmsg)
  -%% on an IPv4 TCP (stream) socket.
  +%% on an Unix Domain (stream) socket (TCP).
   api_b_sendmsg_and_recvmsg_tcpL(suite) ->
       [];
   api_b_sendmsg_and_recvmsg_tcpL(doc) ->
  
positive.code:                                   socket:recv(Sock)
                            end,
                     InitState = #{domain => local,
                                   type   => stream,
                                   proto  => default,
                                   send   => Send,
                                   recv   => Recv},
  
negative.code:      api_b_open_and_close_udpL,
       api_b_open_and_close_tcpL,
       api_b_sendto_and_recvfrom_udp4,
       api_b_sendto_and_recvfrom_udpL,
       api_b_sendmsg_and_recvmsg_udp4,
       api_b_send_and_recv_tcp4,
       api_b_send_and_recv_tcpL,
  