# File src/ruby_supportlib/phusion_passenger/utils/progress_bar.rb, line 36
    def set(percentage)
      if @tty
        width = (percentage * 50).to_i
        bar   = "*" * width
        space = " " * (50 - width)
        text = sprintf("[%s%s] %s", bar, space, THROBBLER[@throbbler_index])
        @throbbler_index = (@throbbler_index + 1) % THROBBLER.size
        @output.write("#{text}\r")
        @output.flush
      else
        @output.write(".")
        @output.flush
      end
    end