+this allows the cipher list sent by the client to be modified. Although
+the server determines which cipher suite is used it should take the first
+supported cipher in the list sent by the client. See the B<ciphers>
+command for more information.
+
+=item B<-starttls protocol>
+
+send the protocol-specific message(s) to switch to TLS for communication.
+B<protocol> is a keyword for the intended protocol. Currently, the only
+supported keywords are "smtp", "pop3", "imap", "ftp", "xmpp",
+and "xmpp-server".
+
+=item B<-xmpphost hostname>
+
+This option, when used with "-starttls xmpp" or "-starttls xmpp-server",
+specifies the host for the "to" attribute of the stream element.
+If this option is not specified, then the host specified with "-connect"
+will be used.
+
+=item B<-tlsextdebug>
+
+print out a hex dump of any TLS extensions received from the server.
+
+=item B<-no_ticket>
+
+disable RFC4507bis session ticket support.
+
+=item B<-sess_out filename>
+
+output SSL session to B<filename>
+
+=item B<-sess_in sess.pem>
+
+load SSL session from B<filename>. The client will attempt to resume a
+connection from this session.
+
+=item B<-engine id>
+
+specifying an engine (by its unique B<id> string) will cause B<s_client>
+to attempt to obtain a functional reference to the specified engine,
+thus initialising it if needed. The engine will then be set as the default
+for all available algorithms.
+
+=item B<-rand file(s)>
+
+a file or files containing random data used to seed the random number
+generator, or an EGD socket (see L<RAND_egd(3)>).
+Multiple files can be specified separated by a OS-dependent character.
+The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
+all others.
+
+=item B<-serverinfo types>
+
+a list of comma-separated TLS Extension Types (numbers between 0 and
+65535). Each type will be sent as an empty ClientHello TLS Extension.
+The server's response (if any) will be encoded and displayed as a PEM
+file.
+
+=item B<-status>
+
+sends a certificate status request to the server (OCSP stapling). The server
+response (if any) is printed out.
+
+=item B<-nextprotoneg protocols>
+
+enable Next Protocol Negotiation TLS extension and provide a list of
+comma-separated protocol names that the client should advertise
+support for. The list should contain most wanted protocols first.
+Protocol names are printable ASCII strings, for example "http/1.1" or
+"spdy/3".
+Empty list of protocols is treated specially and will cause the client to
+advertise support for the TLS extension but disconnect just after
+receiving ServerHello with a list of server supported protocols.