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diff --git a/doc/man3/SSL_shutdown.pod b/doc/man3/SSL_shutdown.pod
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+++ b/doc/man3/SSL_shutdown.pod
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+=pod
+
+=head1 NAME
+
+SSL_shutdown - shut down a TLS/SSL connection
+
+=head1 SYNOPSIS
+
+ #include <openssl/ssl.h>
+
+ int SSL_shutdown(SSL *ssl);
+
+=head1 DESCRIPTION
+
+SSL_shutdown() shuts down an active TLS/SSL connection. It sends the
+"close notify" shutdown alert to the peer.
+
+=head1 NOTES
+
+SSL_shutdown() tries to send the "close notify" shutdown alert to the peer.
+Whether the operation succeeds or not, the SSL_SENT_SHUTDOWN flag is set and
+a currently open session is considered closed and good and will be kept in the
+session cache for further reuse.
+
+The shutdown procedure consists of 2 steps: the sending of the "close notify"
+shutdown alert and the reception of the peer's "close notify" shutdown
+alert. According to the TLS standard, it is acceptable for an application
+to only send its shutdown alert and then close the underlying connection
+without waiting for the peer's response (this way resources can be saved,
+as the process can already terminate or serve another connection).
+When the underlying connection shall be used for more communications, the
+complete shutdown procedure (bidirectional "close notify" alerts) must be
+performed, so that the peers stay synchronized.
+
+SSL_shutdown() supports both uni- and bidirectional shutdown by its 2 step
+behaviour.
+
+SSL_shutdown() only closes the write direction.
+It is not possible to call SSL_write() after calling SSL_shutdown().
+The read direction is closed by the peer.
+
+=head2 First to close the connection
+
+When the application is the first party to send the "close notify"
+alert, SSL_shutdown() will only send the alert and then set the
+SSL_SENT_SHUTDOWN flag (so that the session is considered good and will
+be kept in the cache).
+SSL_shutdown() will then return with 0.
+If a unidirectional shutdown is enough (the underlying connection shall be
+closed anyway), this first call to SSL_shutdown() is sufficient.
+
+In order to complete the bidirectional shutdown handshake, the peer needs
+to send back a "close notify" alert.
+The SSL_RECEIVED_SHUTDOWN flag will be set after receiving and processing
+it.
+SSL_shutdown() will return 1 when it has been received.
+
+The peer is still allowed to send data after receiving the "close notify"
+event.
+If the peer did send data it needs to be processed by calling SSL_read()
+before calling SSL_shutdown() a second time.
+SSL_read() will indicate the end of the peer data by returning <= 0
+and SSL_get_error() returning SSL_ERROR_ZERO_RETURN.
+It is recommended to call SSL_read() between SSL_shutdown() calls.
+
+=head2 Peer closes the connection
+
+If the peer already sent the "close notify" alert B<and> it was
+already processed implicitly inside another function
+(L<SSL_read(3)>), the SSL_RECEIVED_SHUTDOWN flag is set.
+SSL_read() will return <= 0 in that case, and SSL_get_error() will return
+SSL_ERROR_ZERO_RETURN.
+SSL_shutdown() will send the "close notify" alert, set the SSL_SENT_SHUTDOWN
+flag and will immediately return with 1.
+Whether SSL_RECEIVED_SHUTDOWN is already set can be checked using the
+SSL_get_shutdown() (see also L<SSL_set_shutdown(3)> call.
+
+=head1 NOTES
+
+It is recommended to do a bidirectional shutdown by checking the return value
+of SSL_shutdown() and call it again until it returns 1 or a fatal error.
+
+The behaviour of SSL_shutdown() additionally depends on the underlying BIO.
+If the underlying BIO is B<blocking>, SSL_shutdown() will only return once the
+handshake step has been finished or an error occurred.
+
+If the underlying BIO is B<non-blocking>, SSL_shutdown() will also return
+when the underlying BIO could not satisfy the needs of SSL_shutdown()
+to continue the handshake. In this case a call to SSL_get_error() with the
+return value of SSL_shutdown() will yield B<SSL_ERROR_WANT_READ> or
+B<SSL_ERROR_WANT_WRITE>. The calling process then must repeat the call after
+taking appropriate action to satisfy the needs of SSL_shutdown().
+The action depends on the underlying BIO. When using a non-blocking socket,
+nothing is to be done, but select() can be used to check for the required
+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.
+
+SSL_shutdown() can be modified to only set the connection to "shutdown"
+state but not actually send the "close notify" alert messages,
+see L<SSL_CTX_set_quiet_shutdown(3)>.
+When "quiet shutdown" is enabled, SSL_shutdown() will always succeed
+and return 1.
+
+=head1 RETURN VALUES
+
+The following return values can occur:
+
+=over 4
+
+=item Z<>0
+
+The shutdown is not yet finished: the "close notify" was send but the peer
+did not send it back yet.
+Call SSL_shutdown() again to do a bidirectional shutdown.
+The output of L<SSL_get_error(3)> may be misleading, as an
+erroneous SSL_ERROR_SYSCALL may be flagged even though no error occurred.
+
+=item Z<>1
+
+The shutdown was successfully completed. The "close notify" alert was sent
+and the peer's "close notify" alert was received.
+
+=item E<lt>0
+
+The shutdown was not successful.
+Call L<SSL_get_error(3)> with the return value B<ret> to find out the reason.
+It can occur if an action is needed to continue the operation for non-blocking
+BIOs.
+
+It can also occur when not all data was read using SSL_read().
+
+=back
+
+=head1 SEE ALSO
+
+L<SSL_get_error(3)>, L<SSL_connect(3)>,
+L<SSL_accept(3)>, L<SSL_set_shutdown(3)>,
+L<SSL_CTX_set_quiet_shutdown(3)>,
+L<SSL_clear(3)>, L<SSL_free(3)>,
+L<ssl(7)>, L<bio(7)>
+
+=head1 COPYRIGHT
+
+Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (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>.
+
+=cut