.. efun:: void ed()
  void ed(string file)
  void ed(string file, string func)

  Calling without arguments will start the editor ed with the name of the error file, that was returned by ``master->valid_read(0, geteuid(this_player()), "ed_start", this_player())``, usually something like ``~/.err``. If that file is empty, ed will immediatly exit again. Calling :efun:`ed` with :arg:`file` will start the editor on the specified path. If the optional argument func is given, this function will be called after exiting the editor.

  The editor ed is almost ``ed(1)`` compatible.

  .. todo:: is above meaningful to an average builder?

  .. seealso:: :efun:`enable_commands`, :efun:`query_editing`, :guide:`ed`