title: Location of ini/config files in linux/unix?
body: <p>Two questions, really:</p>
  
  <ol>
  <li><p>Is there a standard/convention regarding the placement on configuration files?  </p>
  
  <p>For system or quasi-system programs they seem to usually be somewhere in <code>/etc</code>.  It seems less clear for plain application programs or programs with insufficient privileges for <code>/etc</code>.</p></li>
  <li><p>In processing program options is there a standard hierarchy of what takes precedence?  E.g. does a command line option override an initialization file and/or an environment variable?  Vice versa?  Or is this entirely up to the developer?</p></li>
  </ol>