anchor.diff:      parse_args(Tail, [sasl | Acc]);
   parse_args(["--hup" | Tail], Acc) ->
       parse_args(Tail, [hup | Acc]);
  +parse_args(["--ping" | Tail], Acc) ->
  +    parse_args(Tail, [ping | Acc]);
   parse_args(["--", ConfigFilePath], Acc) ->
       [{config, ConfigFilePath} | Acc];
   parse_args(["-" ++ _ = Option | _Tail], _Acc) ->
  
positive.code: 
  -type parsed_args() :: [parsed_arg()].
  
  -type parsed_arg() :: sasl | hup | {config, file:filename()}.
  
  %% --------------------------------------------------------------------
  %% API functions
  
negative.code:       "  ~s /path/to/config~n"
        "\tStart Erjik;~n"
        "  ~s --hup /path/to/config~n"
        "\tSend reconfig signal to running Erjik instance;~n"
        "  ~s --ping /path/to/config~n"
        "\tCheck if Erjik instance is alive or not.~n",
        [version(), N, N, N, N]),
      halt().
  
  %% @doc Return epv version.
  