condition. When using a buffering BIO, like a BIO pair, data must be written
into or retrieved out of the BIO before being able to continue.
+Many systems implement Nagle's algorithm by default which means that it will
+buffer outgoing TCP data if a TCP packet has already been sent for which no
+corresponding ACK has been received yet from the peer. This can have performance
+impacts after a successful TLSv1.3 handshake or a successful TLSv1.2 (or below)
+resumption handshake, because the last peer to communicate in the handshake is
+the client. If the client is also the first to send application data (as is
+typical for many protocols) then this data could be buffered until an ACK has
+been received for the final handshake message.
+
+The B<TCP_NODELAY> socket option is often available to disable Nagle's
+algorithm. If an application opts to disable Nagle's algorithm consideration
+should be given to turning it back on again later if appropriate. The helper
+function BIO_set_tcp_ndelay() can be used to turn on or off the B<TCP_NODELAY>
+option.
+
=head1 RETURN VALUES
The following return values can occur:
The TLS/SSL handshake was not successful, because a fatal error occurred either
at the protocol level or a connection failure occurred. The shutdown was
-not clean. It can also occur of action is need to continue the operation
+not clean. It can also occur if action is needed to continue the operation
for non-blocking BIOs. Call SSL_get_error() with the return value B<ret>
to find out the reason.
=head1 SEE ALSO
L<SSL_get_error(3)>, L<SSL_accept(3)>,
-L<SSL_shutdown(3)>, L<ssl(3)>, L<bio(3)>,
+L<SSL_shutdown(3)>, L<ssl(7)>, L<bio(7)>,
L<SSL_set_connect_state(3)>,
L<SSL_do_handshake(3)>,
L<SSL_CTX_new(3)>
=head1 COPYRIGHT
-Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
-Licensed under the OpenSSL license (the "License"). You may not use
+Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.