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diff --git a/doc/man3/SSL_read.pod b/doc/man3/SSL_read.pod
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+=pod
+
+=head1 NAME
+
+SSL_read_ex, SSL_read, SSL_peek_ex, SSL_peek
+- read bytes from a TLS/SSL connection
+
+=head1 SYNOPSIS
+
+ #include <openssl/ssl.h>
+
+ int SSL_read_ex(SSL *ssl, void *buf, size_t num, size_t *readbytes);
+ int SSL_read(SSL *ssl, void *buf, int num);
+
+ int SSL_peek_ex(SSL *ssl, void *buf, size_t num, size_t *readbytes);
+ int SSL_peek(SSL *ssl, void *buf, int num);
+
+=head1 DESCRIPTION
+
+SSL_read_ex() and SSL_read() try to read B<num> bytes from the specified B<ssl>
+into the buffer B<buf>. On success SSL_read_ex() will store the number of bytes
+actually read in B<*readbytes>.
+
+SSL_peek_ex() and SSL_peek() are identical to SSL_read_ex() and SSL_read()
+respectively except no bytes are actually removed from the underlying BIO during
+the read, so that a subsequent call to SSL_read_ex() or SSL_read() will yield
+at least the same bytes.
+
+=head1 NOTES
+
+In the paragraphs below a "read function" is defined as one of SSL_read_ex(),
+SSL_read(), SSL_peek_ex() or SSL_peek().
+
+If necessary, a read function will negotiate a TLS/SSL session, if not already
+explicitly performed by L<SSL_connect(3)> or L<SSL_accept(3)>. If the
+peer requests a re-negotiation, it will be performed transparently during
+the read function operation. The behaviour of the read functions depends on the
+underlying BIO.
+
+For the transparent negotiation to succeed, the B<ssl> must have been
+initialized to client or server mode. This is being done by calling
+L<SSL_set_connect_state(3)> or SSL_set_accept_state() before the first
+invocation of a read function.
+
+The read functions work based on the SSL/TLS records. The data are received in
+records (with a maximum record size of 16kB). Only when a record has been
+completely received, can it be processed (decryption and check of integrity).
+Therefore data that was not retrieved at the last read call can still be
+buffered inside the SSL layer and will be retrieved on the next read
+call. If B<num> is higher than the number of bytes buffered then the read
+functions will return with the bytes buffered. If no more bytes are in the
+buffer, the read functions will trigger the processing of the next record.
+Only when the record has been received and processed completely will the read
+functions return reporting success. At most the contents of one record will
+be returned. As the size of an SSL/TLS record may exceed the maximum packet size
+of the underlying transport (e.g. TCP), it may be necessary to read several
+packets from the transport layer before the record is complete and the read call
+can succeed.
+
+If B<SSL_MODE_AUTO_RETRY> has been switched off and a non-application data
+record has been processed, the read function can return and set the error to
+B<SSL_ERROR_WANT_READ>.
+In this case there might still be unprocessed data available in the B<BIO>.
+If read ahead was set using L<SSL_CTX_set_read_ahead(3)>, there might also still
+be unprocessed data available in the B<SSL>.
+This behaviour can be controlled using the L<SSL_CTX_set_mode(3)> call.
+
+If the underlying BIO is B<blocking>, a read function will only return once the
+read operation has been finished or an error occurred, except when a
+non-application data record has been processed and B<SSL_MODE_AUTO_RETRY> is
+not set.
+Note that if B<SSL_MODE_AUTO_RETRY> is set and only non-application data is
+available the call will hang.
+
+If the underlying BIO is B<non-blocking>, a read function will also return when
+the underlying BIO could not satisfy the needs of the function to continue the
+operation.
+In this case a call to L<SSL_get_error(3)> with the
+return value of the read function will yield B<SSL_ERROR_WANT_READ> or
+B<SSL_ERROR_WANT_WRITE>.
+As at any time it's possible that non-application data needs to be sent,
+a read function can also cause write operations.
+The calling process then must repeat the call after taking appropriate action
+to satisfy the needs of the read function.
+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.
+
+L<SSL_pending(3)> can be used to find out whether there
+are buffered bytes available for immediate retrieval.
+In this case the read function can be called without blocking or actually
+receiving new data from the underlying socket.
+
+=head1 RETURN VALUES
+
+SSL_read_ex() and SSL_peek_ex() will return 1 for success or 0 for failure.
+Success means that 1 or more application data bytes have been read from the SSL
+connection.
+Failure means that no bytes could be read from the SSL connection.
+Failures can be retryable (e.g. we are waiting for more bytes to
+be delivered by the network) or non-retryable (e.g. a fatal network error).
+In the event of a failure call L<SSL_get_error(3)> to find out the reason which
+indicates whether the call is retryable or not.
+
+For SSL_read() and SSL_peek() the following return values can occur:
+
+=over 4
+
+=item E<gt> 0
+
+The read operation was successful.
+The return value is the number of bytes actually read from the TLS/SSL
+connection.
+
+=item Z<><= 0
+
+The read operation was not successful, because either the connection was closed,
+an error occurred or action must be taken by the calling process.
+Call L<SSL_get_error(3)> with the return value B<ret> to find out the reason.
+
+Old documentation indicated a difference between 0 and -1, and that -1 was
+retryable.
+You should instead call SSL_get_error() to find out if it's retryable.
+
+=back
+
+=head1 HISTORY
+
+SSL_read_ex() and SSL_peek_ex() were added in OpenSSL 1.1.1.
+
+=head1 SEE ALSO
+
+L<SSL_get_error(3)>, L<SSL_write_ex(3)>,
+L<SSL_CTX_set_mode(3)>, L<SSL_CTX_new(3)>,
+L<SSL_connect(3)>, L<SSL_accept(3)>
+L<SSL_set_connect_state(3)>,
+L<SSL_pending(3)>,
+L<SSL_shutdown(3)>, L<SSL_set_shutdown(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