anchor.diff:          code = 0,
           to_tags = [],
           cancel = undefined,
  -        iter = 1,
  -        meta = []
  +        iter = 1
       },
       Msg = {MsgId, Id, DialogId},
       {UAC, Call#call{trans=[UAC|Trans], msgs=[Msg|Msgs], next=Id+1}}.
  
positive.code:     Call2 = case lists:member(no_dialog, Opts) of
          true -> Call1;
          false when ToTag == <<>> -> Call1;
          false -> nksip_call_uac_dialog:request(Req, IsProxy,  Call1)
      end,
      Call3 = nksip_call_uac_reply:reply({req, Req}, UAC1, Call2),
      sent_update(Req, UAC1, Call3).
  
negative.code:         id = Id,
          status = Status,
          opts = Opts,
          method = Method,
          iter = Iter,
          from = From
      } = UAC,
  