private static void executeCmd(String... cmd) {
        System.out.println("spawning" + Arrays.toString(cmd));
        try {
            ProcessBuilder pb = new ProcessBuilder(cmd);
            Process p = pb.start();
            if (true) {
                InputStream in = p.getInputStream();
                BufferedInputStream buf = new BufferedInputStream(in);
                InputStreamReader inread = new InputStreamReader(buf);
                BufferedReader bufferedreader = new BufferedReader(inread);
                String line;
                while ((line = bufferedreader.readLine()) != null) {
                    System.err.println(line);
                }
            }
            p.waitFor();
        } catch (Exception e) {
            System.err.println("could not execute <" + Arrays.toString(cmd) + ">");
        }
    }