# File lib/rbreadline.rb, line 2111
  def _rl_read_init_file(filename, include_level)
    @current_readline_init_file = filename
    @current_readline_init_include_level = include_level

    openname = File.expand_path(filename)
    begin
      buffer = nil
      File.open(openname) do |file|
        buffer = file.read
      end
    rescue
      return -1
    end

    if (include_level == 0 && filename != @last_readline_init_file)
      @last_readline_init_file = filename.dup
    end

    @currently_reading_init_file = true

    # Loop over the lines in the file.  Lines that start with `#' are
    #   comments; all other lines are commands for readline initialization.
    @current_readline_init_lineno = 1

    buffer.each_line do |line|
      line.strip!
      next if line =~ /^#/
      next if line == ''
      rl_parse_and_bind(line)
    end

    return 0
  end