anchor.diff:  check_request(file_server_2, {read_file_info, _}) -> ok;
   check_request(init, {get_argument, _}) -> ok;
   check_request(init, get_arguments) -> ok;
  -check_request(Name, Other) ->
  -  Request =
  -    try
  -      element(1, Other)
  -    catch
  -      _:_ ->
  -        Other
  -    end,
  -  ?crash({unsupported_request, Name, Request}).
  +check_request(Name, Request) ->
  +  throw({unsupported_request, Name, Request}).
   
   reset_concuerror_info(Info) ->
     #concuerror_info{
  
positive.code:     "data that may differ on separate runs of the program.~n"
      "Location: ~p~n",
      [Module, Name, Arity, Args, M, F, length(OArgs), OArgs, Location]);
  explain_error({unknown_protocol_for_system, System}) ->
    io_lib:format(
      "A process tried to send a message to system process ~p. Concuerror does"
      " not currently support communication with this process. Please contact the"
      " developers for more information.",[System]);
  explain_error({unknown_built_in, {Module, Name, Arity, Location, Stack}}) ->
    LocationString =
      case Location of
  
negative.code:     [Module, Name, Arity, LocationString, Stack]);
  explain_error({unsupported_request, Name, Type}) ->
    io_lib:format(
      "A process send a request of type '~w' to ~p. Concuerror does not yet support"
      " this type of request to this process.",
      [Type, Name]);
  explain_error({wrapper_asked_for_status, Name}) ->
    io_lib:format(
  