title: Which differences are among System.err/out, e.printStackTrace and log for android Exception?
body: <p>I am a little confused to differenate System.err/out, e.printStackTrace and log while logging RuntimeException.</p>
  
  <p>At first, I thought that log information is not saved in a file if I use System.err/out, e.printStackTrace and just printed on console.</p>
  
  <p>But System.err/out, e.printStackTrace also seem to be logged in a log buffer and we can see it through logcat.</p>
  
  <p>Threfore, if we can save log in a file and also System.err/out, e.printStackTrace results can saved in a file.</p>
  
  <p>Q1. What I understand is right?</p>
  
  <p>Q2. If it is, which logging type is better to debug field issues after production?</p>
  
  <p>Q3. If any RuntimeExceptions occur, where can I find the log file in android folder?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>I got an answer for Q3.</p>
  
  <p>In case of android, RuntimeException log seems to be saved in /data/system/dropbox.</p>