code: public static String qx(String... cmd) {
      StringBuilder sb = new StringBuilder();
  
      try {
        Process proc = Runtime.getRuntime().exec(cmd);
        BufferedReader stdInput =
            new BufferedReader(new InputStreamReader(proc.getInputStream()));
        BufferedReader stdError =
            new BufferedReader(new InputStreamReader(proc.getErrorStream()));
  
        String s;
        while ((s = stdInput.readLine()) != null) {
          sb.append(s).append(System.getProperty("line.separator"));
        }
        while ((s = stdError.readLine()) != null) {
          sb.append(s).append(System.getProperty("line.separator"));
        }
      } catch (IOException e) {
        logger.log(Level.SEVERE, null, e);
        throw new RuntimeException(e);
      }
  
      return sb.toString();
    }
docs: Executes a system command and returns its result.
  
  @param cmd
  to be executed
  @return String
  @throws RuntimeException
  if command is not found