docs: private void checkErrorStream(Process process) throws Exception {
  		// rrdtool should use platform encoding (unless you did something
  		// very strange with your installation of rrdtool). So let's be
  		// explicit and use the presumed correct encoding to read errors.
  		try (
  				InputStream is = process.getErrorStream();
  				InputStreamReader isr = new InputStreamReader(is, Charset.defaultCharset());
  				BufferedReader br = new BufferedReader(isr)
  		) {
  			StringBuilder sb = new StringBuilder();
  			String line;
  			while ((line = br.readLine()) != null) {
  				sb.append(line);
  			}
  			if (sb.length() > 0) {
  				throw new RuntimeException(sb.toString());
  			}
  		}
  	}