try {
     Runtime rt = Runtime.getRuntime();
     Process pcs = rt.exec("ls -l /data");
     BufferedReader br = new BufferedReader(new InputStreamReader(pcs
           .getInputStream()));
     String line = null;
     while ((line = br.readLine()) != null) {
        Log.e("line","line="+line);
     }
     br.close();
     pcs.waitFor();
     int ret = pcs.exitValue();
     Log.e("ret","ret="+ret);
  } catch (Exception e) {
     Log.e("Exception", "Exception", e);
  }

only print "ret=0",How to print the correct path?