TELNET(1)                    BSD Reference Manual                    TELNET(1)

NNAAMMEE
     tteellnneett - user interface to the TELNET protocol

SSYYNNOOPPSSIISS
     tteellnneett [--88] [--EE] [--FF] [--KK] [--LL] [--SS _t_o_s] [--XX _a_u_t_h_t_y_p_e] [--aa] [--cc] [--dd] [--ee
            _e_s_c_a_p_e_c_h_a_r] [--ff] [--kk _r_e_a_l_m] [--ll _u_s_e_r] [--nn _t_r_a_c_e_f_i_l_e] [--rr] [--xx]
            [_h_o_s_t [port]]

DDEESSCCRRIIPPTTIIOONN
     The tteellnneett command is used to communicate with another host using the
     TELNET protocol.  If tteellnneett is invoked without the _h_o_s_t argument, it en-
     ters command mode, indicated by its prompt (tteellnneett>>). In this mode, it
     accepts and executes the commands listed below.  If it is invoked with
     arguments, it performs an ooppeenn command with those arguments.

     Options:

     --88      Specifies an 8-bit data path.  This causes an attempt to negoti-
             ate the TELNET BINARY option on both input and output.

     --EE      Stops any character from being recognized as an escape character.

     --FF      If Kerberos V5 authentication is being used, the --FF option allows
             the local credentials to be forwarded to the remote system, in-
             cluding any credentials that have already been forwarded into the
             local environment.

     --KK      Specifies no automatic login to the remote system.

     --LL      Specifies an 8-bit data path on output.  This causes the BINARY
             option to be negotiated on output.

     --SS _t_o_s  Sets the IP type-of-service (TOS) option for the telnet connec-
             tion to the value _t_o_s_, which can be a numeric TOS value or, on
             systems that support it, a symbolic TOS name found in the
             /etc/iptos file.

     --XX _a_t_y_p_e
             Disables the _a_t_y_p_e type of authentication.

     --aa      Attempt automatic login.  Currently, this sends the user name via
             the USER variable of the ENVIRON option if supported by the re-
             mote system.  The name used is that of the current user as re-
             turned by getlogin(2) if it agrees with the current user ID, oth-
             erwise it is the name associated with the user ID.

     --cc      Disables the reading of the user's _._t_e_l_n_e_t_r_c file.  (See the
             ttooggggllee sskkiipprrcc command on this man page.)

     --dd      Sets the initial value of the ddeebbuugg toggle to TRUE

     --ee _e_s_c_a_p_e _c_h_a_r
             Sets the initial tteellnneett tteellnneett escape character to _e_s_c_a_p_e _c_h_a_r_.
             If _e_s_c_a_p_e _c_h_a_r is omitted, then there will be no escape charac-
             ter.

     --ff      If Kerberos V5 authentication is being used, the --ff option allows
             the local credentials to be forwarded to the remote system.

     --kk _r_e_a_l_m
             If Kerberos authentication is being used, the --kk option requests
             that telnet obtain tickets for the remote host in realm realm in-
             stead of the remote host's realm, as determined by

             krb_realmofhost(3).

     --ll _u_s_e_r
             When connecting to the remote system, if the remote system under-
             stands the ENVIRON option, then _u_s_e_r will be sent to the remote
             system as the value for the variable USER.  This option implies
             the --aa option.  This option may also be used with the ooppeenn com-
             mand.

     --nn _t_r_a_c_e_f_i_l_e
             Opens _t_r_a_c_e_f_i_l_e for recording trace information.  See the sseett
             ttrraacceeffiillee command below.

     --rr      Specifies a user interface similar to rlogin(1).  In this mode,
             the escape character is set to the tilde (~) character, unless
             modified by the -e option.

     --xx      Turns on encryption of the data stream if possible.  This option
             is not available outside of the United States and Canada.

     _h_o_s_t    Indicates the official name, an alias, or the Internet address of
             a remote host.

     _p_o_r_t    Indicates a port number (address of an application).  If a number
             is not specified, the default tteellnneett port is used.

     When in rlogin mode, a line of the form ~.  disconnects from the remote
     host; ~ is the telnet escape character.  Similarly, the line ~^Z suspends
     the telnet session.  The line ~^] escapes to the normal telnet escape
     prompt.

     Once a connection has been opened, tteellnneett will attempt to enable the
     TELNET LINEMODE option.  If this fails, then tteellnneett will revert to one of
     two input modes: either ``character at a time'' or ``old line by line''
     depending on what the remote system supports.

     When LINEMODE is enabled, character processing is done on the local sys-
     tem, under the control of the remote system.  When input editing or char-
     acter echoing is to be disabled, the remote system will relay that infor-
     mation.  The remote system will also relay changes to any special charac-
     ters that happen on the remote system, so that they can take effect on
     the local system.

     In ``character at a time'' mode, most text typed is immediately sent to
     the remote host for processing.

     In ``old line by line'' mode, all text is echoed locally, and (normally)
     only completed lines are sent to the remote host.  The ``local echo char-
     acter'' (initially ``^E'') may be used to turn off and on the local echo
     (this would mostly be used to enter passwords without the password being
     echoed).

     If the LINEMODE option is enabled, or if the llooccaallcchhaarrss toggle is TRUE
     (the default for ``old line by line``; see below), the user's qquuiitt, iinnttrr,
     and fflluusshh characters are trapped locally, and sent as TELNET protocol se-
     quences to the remote side.  If LINEMODE has ever been enabled, then the
     user's ssuusspp and eeooff are also sent as TELNET protocol sequences, and qquuiitt
     is sent as a TELNET ABORT instead of BREAK There are options (see ttooggggllee
     aauuttoofflluusshh and ttooggggllee aauuttoossyynncchh below) which cause this action to flush
     subsequent output to the terminal (until the remote host acknowledges the
     TELNET sequence) and flush previous terminal input (in the case of qquuiitt
     and iinnttrr).

     While connected to a remote host, tteellnneett command mode may be entered by
     typing the tteellnneett ``escape character'' (initially ``^]'').  When in com-
     mand mode, the normal terminal editing conventions are available.

     The following tteellnneett commands are available.  Only enough of each command
     to uniquely identify it need be typed (this is also true for arguments to
     the mmooddee, sseett, ttooggggllee, uunnsseett, ssllcc, eennvviirroonn, and ddiissppllaayy commands).

     aauutthh _a_r_g_u_m_e_n_t _._._.
                The auth command manipulates the information sent through the
                TELNET AUTHENTICATE option.  Valid arguments for the auth com-
                mand are as follows:

                ddiissaabbllee _t_y_p_e  Disables the specified type of authentication.
                              To obtain a list of available types, use the
                              aauutthh ddiissaabbllee ?? command.

                eennaabbllee _t_y_p_e   Enables the specified type of authentication.
                              To obtain a list of available types, use the
                              aauutthh eennaabbllee ?? command.

                ssttaattuuss        Lists the current status of the various types of
                              authentication.

     cclloossee      Close a TELNET session and return to command mode.

     ddiissppllaayy _a_r_g_u_m_e_n_t _._._.
                Displays all, or some, of the sseett and ttooggggllee values (see be-
                low).

     eennccrryypptt _a_r_g_u_m_e_n_t _._._.
                The encrypt command manipulates the information sent through
                the TELNET ENCRYPT option.

                Note:  Because of export controls, the TELNET ENCRYPT option
                is not supported outside of the United States and Canada.

                Valid arguments for the encrypt command are as follows:

                ddiissaabbllee _t_y_p_e [[iinnppuutt||oouuttppuutt]]
                              Disables the specified type of encryption.  If
                              you omit the input and output, both input and
                              output are disabled.  To obtain a list of avail-
                              able types, use the eennccrryypptt ddiissaabbllee ?? command.

                eennaabbllee _t_y_p_e [[iinnppuutt||oouuttppuutt]]
                              Enables the specified type of encryption.  If
                              you omit input and output, both input and output
                              are enabled.  To obtain a list of available
                              types, use the eennccrryypptt eennaabbllee ?? command.

                iinnppuutt         This is the same as the eennccrryypptt ssttaarrtt iinnppuutt com-
                              mand.

                --iinnppuutt        This is the same as the eennccrryypptt ssttoopp iinnppuutt com-
                              mand.

                oouuttppuutt        This is the same as the eennccrryypptt ssttaarrtt oouuttppuutt
                              command.

                --oouuttppuutt       This is the same as the eennccrryypptt ssttoopp oouuttppuutt com-
                              mand.

                ssttaarrtt [[iinnppuutt||oouuttppuutt]]
                              Attempts to start encryption.  If you omit iinnppuutt
                              and oouuttppuutt,, both input and output are enabled.
                              To obtain a list of available types, use the

                              eennccrryypptt eennaabbllee ?? command.

                ssttaattuuss        Lists the current status of encryption.

                ssttoopp [[iinnppuutt||oouuttppuutt]]
                              Stops encryption.  If you omit input and output,
                              encryption is on both input and output.

                ttyyppee _t_y_p_e     Sets the default type of encryption to be used
                              with later eennccrryypptt ssttaarrtt or eennccrryypptt ssttoopp com-
                              mands.

     eennvviirroonn _a_r_g_u_m_e_n_t_s_._._.
                The eennvviirroonn command is used to manipulate the the variables
                that my be sent through the TELNET ENVIRON option.  The ini-
                tial set of variables is taken from the users environment,
                with only the DISPLAY and PRINTER variables being exported by
                default.  The USER variable is also exported if the --aa or --ll
                options are used.
                Valid arguments for the eennvviirroonn command are:

                ddeeffiinnee _v_a_r_i_a_b_l_e _v_a_l_u_e
                            Define the variable _v_a_r_i_a_b_l_e to have a value of
                            _v_a_l_u_e_. Any variables defined by this command are
                            automatically exported.  The _v_a_l_u_e may be enclosed
                            in single or double quotes so that tabs and spaces
                            may be included.

                uunnddeeffiinnee _v_a_r_i_a_b_l_e
                            Remove _v_a_r_i_a_b_l_e from the list of environment vari-
                            ables.

                eexxppoorrtt _v_a_r_i_a_b_l_e
                            Mark the variable _v_a_r_i_a_b_l_e to be exported to the
                            remote side.

                uunneexxppoorrtt _v_a_r_i_a_b_l_e
                            Mark the variable _v_a_r_i_a_b_l_e to not be exported un-
                            less explicitly asked for by the remote side.

                lliisstt        List the current set of environment variables.
                            Those marked with a ** will be sent automatically,
                            other variables will only be sent if explicitly
                            requested.

                ??           Prints out help information for the eennvviirroonn com-
                            mand.

     llooggoouutt     Sends the TELNET LOGOUT option to the remote side.  This com-
                mand is similar to a cclloossee command; however, if the remote
                side does not support the LOGOUT option, nothing happens.  If,
                however, the remote side does support the LOGOUT option, this
                command should cause the remote side to close the TELNET con-
                nection.  If the remote side also supports the concept of sus-
                pending a user's session for later reattachment, the logout
                argument indicates that you should terminate the session imme-
                diately.

     mmooddee _t_y_p_e  _T_y_p_e is one of several options, depending on the state of the
                TELNET session.  The remote host is asked for permission to go
                into the requested mode.  If the remote host is capable of en-
                tering that mode, the requested mode will be entered.

                cchhaarraacctteerr     Disable the TELNET LINEMODE option, or, if the
                              remote side does not understand the LINEMODE op-

                              tion, then enter ``character at a time`` mode.

                lliinnee          Enable the TELNET LINEMODE option, or, if the
                              remote side does not understand the LINEMODE op-
                              tion, then attempt to enter ``old-line-by-line``
                              mode.

                iissiigg (--iissiigg)  Attempt to enable (disable) the TRAPSIG mode of
                              the LINEMODE option.  This requires that the
                              LINEMODE option be enabled.

                eeddiitt (--eeddiitt)  Attempt to enable (disable) the EDIT mode of the
                              LINEMODE option.  This requires that the
                              LINEMODE option be enabled.

                ssooffttttaabbss (--ssooffttttaabbss)
                              Attempt to enable (disable) the SOFT_TAB mode of
                              the LINEMODE option.  This requires that the
                              LINEMODE option be enabled.

                lliitteecchhoo (--lliitteecchhoo)
                              Attempt to enable (disable) the LIT_ECHO mode of
                              the LINEMODE option.  This requires that the
                              LINEMODE option be enabled.

                ??             Prints out help information for the mmooddee com-
                              mand.

     ooppeenn _h_o_s_t [[--ll] _u_s_e_r][--_p_o_r_t]
                Open a connection to the named host.  If no port number is
                specified, tteellnneett will attempt to contact a TELNET server at
                the default port.  The host specification may be either a host
                name (see hosts(5))  or an Internet address specified in the
                ``dot notation'' (see inet(3)).  The [--ll] option may be used
                to specify the user name to be passed to the remote system via
                the ENVIRON option.  When connecting to a non-standard port,
                tteellnneett omits any automatic initiation of TELNET options.  When
                the port number is preceded by a minus sign, the initial op-
                tion negotiation is done.  After establishing a connection,
                the file _._t_e_l_n_e_t_r_c in the users home directory is opened.
                Lines beginning with a # are comment lines.  Blank lines are
                ignored.  Lines that begin without white space are the start
                of a machine entry.  The first thing on the line is the name
                of the machine that is being connected to.  The rest of the
                line, and successive lines that begin with white space are as-
                sumed to be tteellnneett commands and are processed as if they had
                been typed in manually to the tteellnneett command prompt.

     qquuiitt       Close any open TELNET session and exit tteellnneett. An end of file
                (in command mode) will also close a session and exit.

     sseenndd _a_r_g_u_m_e_n_t_s
                Sends one or more special character sequences to the remote
                host.  The following are the arguments which may be specified
                (more than one argument may be specified at a time):

                aabboorrtt   Sends the TELNET ABORT (Abort processes) sequence.

                aaoo      Sends the TELNET AO (Abort Output) sequence, which
                        should cause the remote system to flush all output
                        _f_r_o_m the remote system _t_o the user's terminal.

                aayytt     Sends the TELNET AYT (Are You There) sequence, to
                        which the remote system may or may not choose to re-


                        spond.

                bbrrkk     Sends the TELNET BRK (Break) sequence, which may have
                        significance to the remote system.

                eecc      Sends the TELNET EC (Erase Character) sequence, which
                        should cause the remote system to erase the last char-
                        acter entered.

                eell      Sends the TELNET EL (Erase Line) sequence, which
                        should cause the remote system to erase the line cur-
                        rently being entered.

                eeooff     Sends the TELNET EOF (End Of File) sequence.

                eeoorr     Sends the TELNET EOR (End of Record) sequence.

                eessccaappee  Sends the current tteellnneett escape character (initially
                        ``^'').

                ggaa      Sends the TELNET GA (Go Ahead) sequence, which likely
                        has no significance to the remote system.

                ggeettssttaattuuss
                        If the remote side supports the TELNET STATUS command,
                        ggeettssttaattuuss will send the subnegotiation to request that
                        the server send its current option status.

                iipp      Sends the TELNET IP (Interrupt Process) sequence,
                        which should cause the remote system to abort the cur-
                        rently running process.

                nnoopp     Sends the TELNET NOP (No OPeration) sequence.

                ssuusspp    Sends the TELNET SUSP (SUSPend process) sequence.

                ssyynncchh   Sends the TELNET SYNCH sequence.  This sequence causes
                        the remote system to discard all previously typed (but
                        not yet read) input.  This sequence is sent as TCP ur-
                        gent data (and may not work if the remote system is a
                        4.2BSD system -- if it doesn't work, a lower case
                        ``r'' may be echoed on the terminal).

                ddoo _c_m_d

                ddoonntt _c_m_d

                wwiillll _c_m_d

                wwoonntt _c_m_d
                        Sends the TELNET DO _c_m_d sequence.  _C_m_d can be either a
                        decimal number between 0 and 255, or a symbolic name
                        for a specific TELNET command.  _C_m_d can also be either
                        hheellpp or ?? to print out help information, including a
                        list of known symbolic names.

                ??       Prints out help information for the sseenndd command.

     sseett _a_r_g_u_m_e_n_t _v_a_l_u_e

     uunnsseett _a_r_g_u_m_e_n_t _v_a_l_u_e
                The sseett command will set any one of a number of tteellnneett vari-
                ables to a specific value or to TRUE. The special value ooffff
                turns off the function associated with the variable, this is
                equivalent to using the uunnsseett command.  The uunnsseett command will
                disable or set to FALSE any of the specified functions.  The
                values of variables may be interrogated with the ddiissppllaayy com-
                mand.  The variables which may be set or unset, but not tog-
                gled, are listed here.  In addition, any of the variables for
                the ttooggggllee command may be explicitly set or unset using the
                sseett and uunnsseett commands.

                aayytt     If TELNET is in localchars mode, or LINEMODE is en-
                        abled, and the status character is typed, a TELNET AYT
                        sequence (see sseenndd aayytt preceding) is sent to the re-
                        mote host.  The initial value for the "Are You There"
                        character is the terminal's status character.

                eecchhoo    This is the value (initially ``^E'') which, when in
                        ``line by line'' mode, toggles between doing local
                        echoing of entered characters (for normal processing),
                        and suppressing echoing of entered characters (for en-
                        tering, say, a password).

                eeooff     If tteellnneett is operating in LINEMODE or ``old line by
                        line'' mode, entering this character as the first
                        character on a line will cause this character to be
                        sent to the remote system.  The initial value of the
                        eof character is taken to be the terminal's eeooff char-
                        acter.

                eerraassee   If tteellnneett is in llooccaallcchhaarrss mode (see ttooggggllee llooccaallcchhaarrss
                        below), aanndd if tteellnneett is operating in ``character at a
                        time'' mode, then when this character is typed, a
                        TELNET EC sequence (see sseenndd eecc above) is sent to the
                        remote system.  The initial value for the erase char-
                        acter is taken to be the terminal's eerraassee character.

                eessccaappee  This is the tteellnneett escape character (initially ``^['')
                        which causes entry into tteellnneett command mode (when con-
                        nected to a remote system).

                fflluusshhoouuttppuutt
                        If tteellnneett is in llooccaallcchhaarrss mode (see ttooggggllee llooccaallcchhaarrss
                        below) and the fflluusshhoouuttppuutt character is typed, a
                        TELNET AO sequence (see sseenndd aaoo above) is sent to the
                        remote host.  The initial value for the flush charac-
                        ter is taken to be the terminal's fflluusshh character.

                ffoorrww11

                ffoorrww22   If TELNET is operating in LINEMODE, these are the
                        characters that, when typed, cause partial lines to be
                        forwarded to the remote system.  The initial value for
                        the forwarding characters are taken from the termi-
                        nal's eol and eol2 characters.

                iinntteerrrruupptt
                        If tteellnneett is in llooccaallcchhaarrss mode (see ttooggggllee llooccaallcchhaarrss
                        below) and the iinntteerrrruupptt character is typed, a TELNET
                        IP sequence (see sseenndd iipp above) is sent to the remote
                        host.  The initial value for the interrupt character
                        is taken to be the terminal's iinnttrr character.

                kkiillll    If tteellnneett is in llooccaallcchhaarrss mode (see ttooggggllee llooccaallcchhaarrss
                        below), aanndd if tteellnneett is operating in ``character at a
                        time'' mode, then when this character is typed, a
                        TELNET EL sequence (see sseenndd eell above) is sent to the
                        remote system.  The initial value for the kill charac-
                        ter is taken to be the terminal's kkiillll character.

                llnneexxtt   If tteellnneett is operating in LINEMODE or ``old line by
                        line`` mode, then this character is taken to be the
                        terminal's llnneexxtt character.  The initial value for the
                        lnext character is taken to be the terminal's llnneexxtt
                        character.

                qquuiitt    If tteellnneett is in llooccaallcchhaarrss mode (see ttooggggllee llooccaallcchhaarrss
                        below) and the qquuiitt character is typed, a TELNET BRK
                        sequence (see sseenndd bbrrkk above) is sent to the remote
                        host.  The initial value for the quit character is
                        taken to be the terminal's qquuiitt character.

                rreepprriinntt
                        If tteellnneett is operating in LINEMODE or ``old line by
                        line`` mode, then this character is taken to be the
                        terminal's rreepprriinntt character.  The initial value for
                        the reprint character is taken to be the terminal's
                        rreepprriinntt character.

                rrllooggiinn  This is the rlogin escape character.  If set, the nor-
                        mal TELNET escape character is ignored unless it is
                        preceded by this character at the beginning of a line.
                        This character, at the beginning of a line followed by
                        a "."  closes the connection; when followed by a ^Z it
                        suspends the telnet command.  The initial state is to
                        disable the rlogin escape character.

                ssttaarrtt   If the TELNET TOGGLE-FLOW-CONTROL option has been en-
                        abled, then this character is taken to be the termi-
                        nal's ssttaarrtt character.  The initial value for the kill
                        character is taken to be the terminal's ssttaarrtt charac-
                        ter.

                ssttoopp    If the TELNET TOGGLE-FLOW-CONTROL option has been en-
                        abled, then this character is taken to be the termi-
                        nal's ssttoopp character.  The initial value for the kill
                        character is taken to be the terminal's ssttoopp charac-
                        ter.

                ssuusspp    If tteellnneett is in llooccaallcchhaarrss mode, or LINEMODE is en-
                        abled, and the ssuussppeenndd character is typed, a TELNET
                        SUSP sequence (see sseenndd ssuusspp above) is sent to the re-
                        mote host.  The initial value for the suspend charac-
                        ter is taken to be the terminal's ssuussppeenndd character.

                ttrraacceeffiillee
                        This is the file to which the output, caused by
                        nneettddaattaa or ooppttiioonn tracing being TRUE, will be written.
                        If it is set to ``--'', then tracing information will
                        be written to standard output (the default).

                wwoorrddeerraassee
                        If tteellnneett is operating in LINEMODE or ``old line by
                        line`` mode, then this character is taken to be the
                        terminal's wwoorrddeerraassee character.  The initial value for
                        the worderase character is taken to be the terminal's
                        wwoorrddeerraassee character.

                ??       Displays the legal sseett (uunnsseett) commands.

     ssllcc _s_t_a_t_e  The ssllcc command (Set Local Characters) is used to set or
                change the state of the the special characters when the TELNET
                LINEMODE option has been enabled.  Special characters are
                characters that get mapped to TELNET commands sequences (like
                iipp or qquuiitt) or line editing characters (like eerraassee and kkiillll).


                By default, the local special characters are exported.

                cchheecckk       Verify the current settings for the current spe-
                            cial characters.  The remote side is requested to
                            send all the current special character settings,
                            and if there are any discrepancies with the local
                            side, the local side will switch to the remote
                            value.

                eexxppoorrtt      Switch to the local defaults for the special char-
                            acters.  The local default characters are those of
                            the local terminal at the time when tteellnneett was
                            started.

                iimmppoorrtt      Switch to the remote defaults for the special
                            characters.  The remote default characters are
                            those of the remote system at the time when the
                            TELNET connection was established.

                ??           Prints out help information for the ssllcc command.

     ssttaattuuss     Show the current status of tteellnneett. This includes the peer one
                is connected to, as well as the current mode.

     ttooggggllee _a_r_g_u_m_e_n_t_s _._._.
                Toggle (between TRUE and FALSE) various flags that control how
                tteellnneett responds to events.  These flags may be set explicitly
                to TRUE or FALSE using the sseett and uunnsseett commands listed
                above.  More than one argument may be specified.  The state of
                these flags may be interrogated with the ddiissppllaayy command.
                Valid arguments are:

                aauutthhddeebbuugg     Turns on debugging information for the authenti-
                              cation code.

                aauuttoofflluusshh     If aauuttoofflluusshh and llooccaallcchhaarrss are both TRUE, then
                              when the aaoo, or qquuiitt characters are recognized
                              (and transformed into TELNET sequences; see sseett
                              above for details), tteellnneett refuses to display
                              any data on the user's terminal until the remote
                              system acknowledges (via a TELNET TIMING MARK
                              option) that it has processed those TELNET se-
                              quences.  The initial value for this toggle is
                              TRUE if the terminal user had not done an "stty
                              noflsh", otherwise FALSE (see stty(1)).

                aauuttooddeeccrryypptt   When the TELNET ENCRYPT option is negotiated, by
                              default the actual encryption (decryption) of
                              the data stream does not start automatically.
                              The autoencrypt (autodecrypt) command states
                              that encryption of the output (input) stream
                              should be enabled as soon as possible.

                              Note:  Because of export controls, the TELNET
                              ENCRYPT option is not supported outside the
                              United States and Canada.

                aauuttoollooggiinn     If the remote side supports the TELNET
                              AUTHENTICATION option TELNET attempts to use it
                              to perform automatic authentication.  If the
                              AUTHENTICATION option is not supported, the us-
                              er's login name are propagated through the
                              TELNET ENVIRON option.  This command is the same
                              as specifying _a option on the ooppeenn command.

                aauuttoossyynncchh     If aauuttoossyynncchh and llooccaallcchhaarrss are both TRUE, then
                              when either the iinnttrr or qquuiitt characters is typed
                              (see sseett above for descriptions of the iinnttrr and
                              qquuiitt characters), the resulting TELNET sequence
                              sent is followed by the TELNET SYNCH sequence.
                              This procedure sshhoouulldd cause the remote system to
                              begin throwing away all previously typed input
                              until both of the TELNET sequences have been
                              read and acted upon.  The initial value of this
                              toggle is FALSE.

                bbiinnaarryy        Enable or disable the TELNET BINARY option on
                              both input and output.

                iinnbbiinnaarryy      Enable or disable the TELNET BINARY option on
                              input.

                oouuttbbiinnaarryy     Enable or disable the TELNET BINARY option on
                              output.

                ccrrllff          If this is TRUE, then carriage returns will be
                              sent as <CR><LF>. If this is FALSE, then car-
                              riage returns will be send as <CR><NUL>. The
                              initial value for this toggle is FALSE.

                ccrrmmoodd         Toggle carriage return mode.  When this mode is
                              enabled, most carriage return characters re-
                              ceived from the remote host will be mapped into
                              a carriage return followed by a line feed.  This
                              mode does not affect those characters typed by
                              the user, only those received from the remote
                              host.  This mode is not very useful unless the
                              remote host only sends carriage return, but nev-
                              er line feed.  The initial value for this toggle
                              is FALSE.

                ddeebbuugg         Toggles socket level debugging (useful only to
                              the ssuuppeerr uusseerr). The initial value for this tog-
                              gle is FALSE.

                eennccddeebbuugg      Turns on debugging information for the encryp-
                              tion code.

                llooccaallcchhaarrss    If this is TRUE, then the fflluusshh, iinntteerrrruupptt,
                              qquuiitt, eerraassee, and kkiillll characters (see sseett above)
                              are recognized locally, and transformed into
                              (hopefully) appropriate TELNET control sequences
                              (respectively aaoo, iipp, bbrrkk, eecc, and eell; see sseenndd
                              above).  The initial value for this toggle is
                              TRUE in ``old line by line'' mode, and FALSE in
                              ``character at a time'' mode.  When the LINEMODE
                              option is enabled, the value of llooccaallcchhaarrss is
                              ignored, and assumed to always be TRUE. If
                              LINEMODE has ever been enabled, then qquuiitt is
                              sent as aabboorrtt, and eeooff aanndd are sent as eeooff aanndd
                              ssuusspp, see sseenndd above).

                nneettddaattaa       Toggles the display of all network data (in hex-
                              adecimal format).  The initial value for this
                              toggle is FALSE.

                ooppttiioonnss       Toggles the display of some internal tteellnneett pro-
                              tocol processing (having to do with TELNET op-
                              tions).  The initial value for this toggle is
                              FALSE.

                pprreettttyydduummpp    When the nneettddaattaa toggle is enabled, if
                              pprreettttyydduummpp is enabled the output from the
                              nneettddaattaa command will be formatted in a more user
                              readable format.  Spaces are put between each
                              character in the output, and the beginning of
                              any TELNET escape sequence is preceded by a '*'
                              to aid in locating them.

                sskkiipprrcc        When the skiprc toggle is TRUE, TELNET skips the
                              reading of the _._t_e_l_n_e_t_r_c file in the users home
                              directory when connections are opened.  The ini-
                              tial value for this toggle is FALSE.

                tteerrmmddaattaa      Toggles the display of all terminal data (in
                              hexadecimal format).  The initial value for this
                              toggle is FALSE.

                vveerrbboossee__eennccrryypptt
                              When the vveerrbboossee__eennccrryypptt toggle is TRUE, TELNET
                              prints out a message each time encryption is en-
                              abled or disabled.  The initial value for this
                              toggle is FALSE. Note:  Because of export con-
                              trols, data encryption is not supported outside
                              of the United States and Canada.

                ??             Displays the legal ttooggggllee commands.

     zz          Suspend tteellnneett. This command only works when the user is using
                the csh(1).

     !! [_c_o_m_m_a_n_d]
                Execute a single command in a subshell on the local system.
                If ccoommmmaanndd is omitted, then an interactive subshell is in-
                voked.

     ?? [_c_o_m_m_a_n_d]
                Get help.  With no arguments, tteellnneett prints a help summary.
                If a command is specified, tteellnneett will print the help informa-
                tion for just that command.

EENNVVIIRROONNMMEENNTT
     TTeellnneett uses at least the HOME, SHELL, DISPLAY, and TERM environment vari-
     ables.  Other environment variables may be propagated to the other side
     via the TELNET ENVIRON option.

FFIILLEESS
     ~/.telnetrc  user customized telnet startup values

HHIISSTTOORRYY
     The TTeellnneett command appeared in 4.2BSD.

NNOOTTEESS
     On some remote systems, echo has to be turned off manually when in ``old
     line by line'' mode.

     In ``old line by line'' mode or LINEMODE the terminal's eeooff character is
     only recognized (and sent to the remote system) when it is the first
     character on a line.

4.2 Berkeley Distribution      February 3, 1994                             11
