 because the trusted certificate store is misconfigured, or there are missing intermediate CAs, or the issuer is simply unrecognised).</p>

<h1 id="FURTHER-READING">FURTHER READING</h1>

<p>See <a href="../man7/ossl-guide-tls-client-non-block.html">ossl-guide-tls-client-non-block(7)</a> to read a tutorial on how to modify the client developed on this page to support a nonblocking socket.</p>

<p>See <a href="../man7/ossl-guide-tls-server-block.html">ossl-guide-tls-server-block(7)</a> for a tutorial on how t