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<h4 class="subsection">4.2.4 Else</h4>

<p><a name="index-g_t_0023else-90"></a>The &lsquo;<samp><span class="samp">#else</span></samp>&rsquo; directive can be added to a conditional to provide
alternative text to be used if the condition fails.  This is what it
looks like:

<pre class="smallexample">     #if <var>expression</var>
     <var>text-if-true</var>
     #else /* Not <var>expression</var> */
     <var>text-if-false</var>
     #endif /* Not <var>expression</var> */
</pre>
   <p class="noindent">If <var>expression</var> is nonzero, the <var>text-if-true</var> is included and
the <var>text-if-false</var> is skipped.  If <var>expression</var> is zero, the
opposite happens.

   <p>You can use &lsquo;<samp><span class="samp">#else</span></samp>&rsquo; with &lsquo;<samp><span class="samp">#ifdef</span></samp>&rsquo; and &lsquo;<samp><span class="samp">#ifndef</span></samp>&rsquo;, too.

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