Apparently explicitly calling "exit" is not the right way to abort a
running ruby script.

  modify the script_clean method calls to include an error message like this

script_clean("exit","Error while trying to make #{WORKDIR}")
    

  and have the method something like

     # Everything is tidy have we been instructed to exit?
    if arg[0] == "exit"
      raise RuntimeError, arg[1] , "\n"
    end