Where is DEBUG defined in the code?
<p>I looked at a sample code to create a log system on my server... And I found this</p>

<pre><code>#if DEBUG
printf("something here");
#endif
</code></pre>

<p>I know what it does. It prtins something only if DEBUG has been defiend. But where is DEBUG defined? I looked at the all the header files but I could't find DEBUG.. </p>

<p>Also, Could you please provide me a good example or tutorial about designing logging system? </p>

<p>Thanks in advance..</p>
