title: Read command output inside su process
body: <p>firstly I will present my situation.
  I need to execute "su" command in my android app and it works well. Then I need to execute "ls" command and read the output. I'm doing it by getting the output stream from the "su" process and writing my command into it.</p>
  
  <p>And here goes the question. How to read the output of the "ls" process? All I have is the "su" Process object. Getting the input stream from it gives nothing, because "su" doesn't write anything. But "ls" does and I don't know how to access its output messages.</p>
  
  <p>I have searched many sites but I didn't find any solution. Maybe someone will help me:)</p>
  
  <p>Regards</p>