anchor.diff:  %% Transport has been removed.
   l({transport, remove, _} = T, #listener{socket = Sock}) ->
       gen_tcp:close(Sock),
  -    x(T);
  -
  -%% Possibly death of an accepting process monitored in old code.
  -l(_, S) ->
  -    S.
  +    x(T).
   
   %% t/2
   %%
  
positive.code: %% death. However, a link can be unlinked and this is exactly what
  %% gen_tcp seems to so. Links should be left to supervisors.
  
  i({listen = L, Ref, _APid, T}) ->  %% from old code
      i({L, Ref, T});
  
  i({listen, Ref, {Mod, Opts, Addrs}}) ->
      [_] = diameter_config:subscribe(Ref, transport), %% assert existence
      {[LA, LP], Rest} = proplists:split(Opts, [ip, port]),
  
negative.code: %% Put the reference in the process dictionary since we now use it
  %% advertise the ssl socket after TLS upgrade.
  
  %% A monitor process to kill the transport if the parent dies.
  i(#monitor{parent = Pid, transport = TPid} = S) ->
      proc_lib:init_ack({ok, self()}),
  