title: Is it possible to check the value of defined statement using C preprocessor?
body: <p>Let's say I have a <code>#define RTR r2</code> statement. Is it possible to check the <strong>value</strong> of the <code>RTR</code> macro? I'm looking something like this:</p>
  
  <pre><code>#if RTR == r1 || RTR == r2
  It is router1 or router2!
  #endif
  </code></pre>
  
  <p>I guess this is not possible..</p>