anchor.diff:    nic_ipv4(Device,T).
   
   
  +%%--------------------------------------------------------------------
  +%% @doc
  +%% Return the formatted IPv4 address out of the list of addresses
  +%% for the interface.
  +%% @end
  +%%--------------------------------------------------------------------
  +-spec nic_ipv4_address([ifopt()]) -> {ok, string()} | {error, not_found}.
   nic_ipv4_address([]) -> {error, not_found};
  -nic_ipv4_address([{addr, {A,B,C,D}}|T]) ->
  +nic_ipv4_address([{addr, {A,B,C,D}}|_]) ->
     inet_parse:ntoa({A,B,C,D});
   nic_ipv4_address([_|T]) ->
     nic_ipv4_address(T).
  -
   
   
   %%--------------------------------------------------------------------
  
positive.code: backend_module(etcd)         -> autocluster_etcd;
  backend_module(_)            -> undefined.
  
  %%--------------------------------------------------------------------
  %% @doc
  %% Return the IP address for the current node for the specified
  
negative.code:   {ok, Interfaces} = inet:getifaddrs(),
    nic_ipv4(Device, Interfaces).
  
  
  %%--------------------------------------------------------------------
  %% @doc
  %% Parse the interface out of the list of interfaces, returning the
  %% IPv4 address if found.
  %% @end
  %%--------------------------------------------------------------------
  -spec nic_ipv4(Device :: string(), Interfaces :: list())
      -> {ok, string()} | {error, not_found}.
  nic_ipv4(_, []) -> {error, not_found};
  nic_ipv4(Device, [{Interface, Opts}|_]) when Interface =:= Device ->
    {ok, nic_ipv4_address(Opts)};
  