et and the private key does not belong to the certificate an error is returned. To change a [certificate/private-key] pair, the new certificate needs to be set first with SSL_use_certificate() or SSL_CTX_use_certificate() before setting the private key with SSL_CTX_use_PrivateKey() or SSL_use_PrivateKey().</p>

<p>SSL_CTX_use_cert_and_key() and SSL_use_cert_and_key() assign the X.509 certificate <b>x</b>, private key <b>key</b>, and certificate <b>chain</b> onto the corresponding <b>ssl</b> or <b>ctx</b>. T