anchor.diff:    Fns = #input_port_fns
       {close = fun ktrue/1,
        read_char = fun input_string_read_char/1,
  -     peek_char = fun input_string_peek_char/1,
  -     is_char_ready = fun ktrue/1},
  +     peek_char = fun input_string_peek_char/1},
     open_input_port(State, Fns).
   
   input_string_read_char(S = {B, I}) ->
  
positive.code:   Fns = #input_port_fns
      {close = fun ktrue/1,
       read_char = fun stdin_read_char/1,
       peek_char = fun stdin_peek_char/1,
       is_char_ready = fun stdin_is_char_ready/1},
    open_input_port(State, Fns).
  
  stdin_read_char(State) ->
  
negative.code: %%% -*- erlang-indent-level: 2 -*-
  %%%
  %%%   Copyright 2014-2022 Mikael Pettersson
  %%%
  %%%   Licensed under the Apache License, Version 2.0 (the "License");
  %%%   you may not use this file except in compliance with the License.
  