class="nroffsh">AVAILABILITY</h2>
<p class="level0">Added in 7.10.7 <a name="RETURN"></a><h2 class="nroffsh">RETURN VALUE</h2>
<p class="level0">Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or CURLE_NOT_BUILT_IN if the bitmask specified no supported authentication methods. <a name="SEE"></a><h2 class="nroffsh">SEE ALSO</h2>
<p class="level0"><a Class="manpage" href="./CURLOPT_PROXY.html">CURLOPT_PROXY</a> <a Class="manpage" href="./CURLOPT_PROXYTYPE.html">CURLOPT_PROXYTYPE</a> <