Only use this in explicit fallback retries, following the guidance
in draft-ietf-tls-downgrade-scsv-00.
+=item SSL_MODE_ASYNC
+
+Enable asynchronous processing. TLS I/O operations may indicate a retry with
+SSL_ERROR_WANT_ASYNC with this mode set if an asynchronous capable engine is
+used to perform cryptographic operations. See L<SSL_get_error(3)>.
+
=back
=head1 RETURN VALUES
=head1 SEE ALSO
-L<ssl(3)>, L<SSL_read(3)>, L<SSL_write(3)>
+L<ssl(3)>, L<SSL_read(3)>, L<SSL_write(3)>, L<SSL_get_error(3)>
+=======
=head1 HISTORY
-SSL_MODE_AUTO_RETRY as been added in OpenSSL 0.9.6.
+SSL_MODE_ASYNC was first added to OpenSSL 1.1.0.
=cut