title: Read android system file
body: <p>I have tried many solutions to read files but no one were working.
  I need a method to read a system file and show the text in a toast or in a dialog.
  Of course my app has root permission.
  I have to show the content of "eoc_status" in a toast  after a checkbox click.</p>
  
  <p>For example;</p>
  
  <pre><code>Runtime.getRuntime().exec("/sys/kernel/abb-chargalg/eoc_status").getInputStream(); 
  </code></pre>
  
  <p>I need to open text files.</p>