module Kernel
  unless method_defined?(:capture)
    def capture(stream)
      stream = stream.to_s
      captured_stream = Tempfile.new(stream)
      stream_io = eval("$#{stream}")
      origin_stream = stream_io.dup
      stream_io.reopen(captured_stream)

      yield

      stream_io.rewind
      return captured_stream.read
    ensure
      captured_stream.unlink
      stream_io.reopen(origin_stream)
    end
  end
end