On the client, before the handshake</dt>
<dd>

<p>If a servername has been set via a call to SSL_set_tlsext_host_name() then it will return that servername.</p>

<p>If one has not been set, but a TLSv1.2 resumption is being attempted and the session from the original handshake had a servername accepted by the server then it will return that servername.</p>

<p>Otherwise it returns NULL.</p>

</dd>
<dt id="On-the-client-during-or-after-the-handshake-and-a-TLSv1.2-or-below-resumption-occurred">On the client, 