public Pair<Integer, String> exec(String command) throws IOException {
        StringTokenizer tok = new StringTokenizer(command);
        List<String> tokens = new ArrayList<>();
        while (tok.hasMoreElements())
            tokens.add(tok.nextToken());
        return exec(tokens.toArray(new String[0]));
    }
Executes the given command synchronously without timeout.

@return retcode and stdout/stderr merged
vespajlib/src/main/java/com/yahoo/system/ProcessExecuter.java