def next_tempfile
      p = nil
      Tempfile.open("onix") do |tf|
        p = tf.path
        tf.close!
      end
      p
    end
def next_tempfile
      p = nil
      Tempfile.open("onix") do |tf|
        p = tf.path
        tf.close!
      end
      p
    end
generate a temp filename