title: android open("/dev/input/event1", O_RDWR); with permission denied?
body: <p>I want to write touchscreen events into ‘/dev/input/event1’，but it  runs  'open("/dev/input/event1", O_RDWR);' with permission denied.My phone has rooted and I acquired  root with code :</p>
  
  <pre><code>String apkRoot="chmod 777 "+getPackageCodePath();
      RootCommand(apkRoot);
  
  public static boolean RootCommand(String command)
  {
      Process process = null;
      DataOutputStream os = null;
      try
      {
          process = Runtime.getRuntime().exec("su");
          os = new DataOutputStream(process.getOutputStream());
          os.writeBytes(command + "\n");
          os.writeBytes("exit\n");
          os.flush();
          process.waitFor();
      } catch (Exception e)
      {
          Log.d("*** DEBUG ***", "ROOT REE" + e.getMessage());
          return false;
      } finally
      {
          try
          {
              if (os != null)
              {
                  os.close();
              }
              process.destroy();
          } catch (Exception e)
          {
          }
      }
      Log.d("*** DEBUG ***", "Root SUC ");
      return true;
  }
  </code></pre>
  
  <p>and it shows that my app acquired root indeed,but I am confused about 'permission denied'.</p>