3>
<pre class="programlisting"><a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
cairo_region_union (<em class="parameter"><code><a class="link" href="cairo-Regions.html#cairo-region-t" title="cairo_region_t"><span class="type">cairo_region_t</span></a> *dst</code></em>,
                    <em class="parameter"><code>const <a class="link" href="cairo-Regions.html#cairo-region-t" title="cairo_region_t"><span class=