=head1 DESCRIPTION
Reset B<ssl> to allow another connection. All settings (method, ciphers,
-BIOs) are kept. A completely negotiated B<SSL_SESSION> is not freed but left
-untouched for the underlying B<SSL_CTX>.
+BIOs) are kept.
+
+=head1 NOTES
+
+SSL_clear is used to prepare an SSL object for a new connection. While all
+settings are kept, a side effect is the handling of the current SSL session.
+If a session is still B<open>, it is considered bad and will be removed
+from the session cache, as required by RFC2246. A session is considered open,
+if L<SSL_shutdown(3)|SSL_shutdown(3)> was not called for the connection
+or at least L<SSL_set_shutdown(3)|SSL_set_shutdown(3)> was used to
+set the SSL_SENT_SHUTDOWN state.
+
+If a session was closed cleanly, the session object will be kept and all
+settings corresponding. This explicitly means, that e.g. the special method
+used during the session will be kept for the next handshake. So if the
+session was a TLSv1 session, a SSL client object will use a TLSv1 client
+method for the next handshake and a SSL server object will use a TLSv1
+server method, even if SSLv23_*_methods were chosen on startup. This
+will might lead to connection failures (see L<SSL_new(3)|SSL_new(3)>)
+for a description of the method's properties.
+
+=head1 WARNINGS
+
+SSL_clear() resets the SSL object to allow for another connection. The
+reset operation however keeps several settings of the last sessions
+(some of these settings were made automatically during the last
+handshake). It only makes sense for a new connection with the exact
+same peer that shares these settings, and may fail if that peer
+changes its settings between connections. Use the sequence
+L<SSL_get_session(3)|SSL_get_session(3)>;
+L<SSL_new(3)|SSL_new(3)>;
+L<SSL_set_session(3)|SSL_set_session(3)>;
+L<SSL_free(3)|SSL_free(3)>
+instead to avoid such failures
+(or simply L<SSL_free(3)|SSL_free(3)>; L<SSL_new(3)|SSL_new(3)>
+if session reuse is not desired).
=head1 RETURN VALUES
=over 4
-=item 0
+=item Z<>0
The SSL_clear() operation could not be performed. Check the error stack to
find out the reason.
-=item 1
+=item Z<>1
The SSL_clear() operation was successful.
=back
L<SSL_new(3)|SSL_new(3)>, L<SSL_free(3)|SSL_free(3)>,
-L<SSL_CTX_set_options(3)|SSL_CTX_set_options(3)>, L<ssl(3)|ssl(3)>
+L<SSL_shutdown(3)|SSL_shutdown(3)>, L<SSL_set_shutdown(3)|SSL_set_shutdown(3)>,
+L<SSL_CTX_set_options(3)|SSL_CTX_set_options(3)>, L<ssl(3)|ssl(3)>,
+L<SSL_CTX_set_client_cert_cb(3)|SSL_CTX_set_client_cert_cb(3)>
=cut