title: how to set permission chmod 777 programatically in android?
body: <p>I want to change the permission programatically in android of the folder <code>/data/system/dropbox</code> so, I have tried it by using </p>
  
  <pre><code>Process pr = Runtime.getRuntime().exec("su chmod 777 /data/system/dropbox");
  </code></pre>
  
  <p>but it is throwing <code>permission denied exception(FileNotFoundException)</code></p>