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diff --git a/upstream/mageia-cauldron/man1/telnet.1 b/upstream/mageia-cauldron/man1/telnet.1 new file mode 100644 index 00000000..ae193957 --- /dev/null +++ b/upstream/mageia-cauldron/man1/telnet.1 @@ -0,0 +1,1509 @@ +.\" $OpenBSD: telnet.1,v 1.27 2000/11/09 17:52:41 aaron Exp $ +.\" $NetBSD: telnet.1,v 1.5 1996/02/28 21:04:12 thorpej Exp $ +.\" +.\" Copyright (c) 1983, 1990, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" from: @(#)telnet.1 8.4 (Berkeley) 2/3/94 +.\" +.Dd February 3, 1994 +.Dt TELNET 1 +.Os +.Sh NAME +.Nm telnet +.Nd user interface to the +.Tn TELNET +protocol +.Sh SYNOPSIS +.Nm telnet +.Op Fl 8EFKLacdfrx +.Op Fl X Ar authtype +.Op Fl b Ar hostalias +.Op Fl e Ar escapechar +.Op Fl k Ar realm +.Op Fl l Ar user +.Op Fl n Ar tracefile +.Oo +.Ar host +.Op Ar port +.Oc +.Sh DESCRIPTION +The +.Nm +command +is used to communicate with another host using the +.Tn TELNET +protocol. +If +.Nm +is invoked without the +.Ar host +argument, it enters command mode, +indicated by its prompt +.Pq Nm telnet\&> . +In this mode, it accepts and executes the commands listed below. +If it is invoked with arguments, it performs an +.Ic open +command with those arguments. +.Pp +The options are as follows: +.Bl -tag -width Ds +.It Fl 7 +Strip 8th bit on input and output. Telnet is 8-bit clean by default but doesn't send the TELNET BINARY option unless forced. +.It Fl 8 +Specifies an 8-bit data path. +This causes an attempt to negotiate the +.Dv TELNET BINARY +option on both input and output. +.It Fl E +Stops any character from being recognized as an escape character. +.It Fl F +If Kerberos V5 authentication is being used, the +.Fl F +option allows the local credentials to be forwarded +to the remote system, including any credentials that +have already been forwarded into the local environment. +.It Fl K +Specifies no automatic login to the remote system. +.It Fl L +Specifies an 8-bit data path on output. +This causes the BINARY option to be negotiated on output. +.It Fl X Ar atype +Disables the +.Ar atype +type of authentication. +.It Fl a +Attempt automatic login. +Currently, this sends the user name via the +.Ev USER +variable +of the +.Ev ENVIRON +option if supported by the remote system. +The name used is that of the current user as returned by +.Xr getlogin 2 +if it agrees with the current user ID, +otherwise it is the name associated with the user ID. +.It Fl b Ar hostalias +Uses +.Xr bind 2 +on the local socket to bind it to an aliased address (see +.Xr ifconfig 8 +and the ``alias'' specifier) or to the address of +another interface than the one naturally chosen by +.Xr connect 2 . +This can be useful when connecting to services which use IP addresses +for authentication and reconfiguration of the server is undesirable (or +impossible). +.It Fl c +Disables the reading of the user's +.Pa \&.telnetrc +file. +(See the +.Ic toggle skiprc +command on this man page.) +.It Fl d +Sets the initial value of the +.Ic debug +toggle to +.Dv TRUE . +.It Fl e Ar escapechar +Sets the initial +.Nm +escape character to +.Ar escapechar Ns . +If +.Ar escapechar +is omitted, then +there will be no escape character. +.It Fl f +If Kerberos V5 authentication is being used, the +.Fl f +option allows the local credentials to be forwarded to the remote system. +.It Fl k Ar realm +If Kerberos authentication is being used, the +.Fl k +option requests that +.Nm +obtain tickets for the remote host in +realm +.Ar realm +instead of the remote host's realm, as determined +by +.Xr krb_realmofhost 3 . +.It Fl l Ar user +When connecting to the remote system, if the remote system +understands the +.Ev ENVIRON +option, then +.Ar user +will be sent to the remote system as the value for the variable USER. +This option implies the +.Fl a +option. +This option may also be used with the +.Ic open +command. +.It Fl n Ar tracefile +Opens +.Ar tracefile +for recording trace information. +See the +.Ic set tracefile +command below. +.It Fl r +Specifies a user interface similar to +.Xr rlogin 1 . +In this +mode, the escape character is set to the tilde (~) character, +unless modified by the +.Fl e +option. +.It Fl x +Turns on encryption of the data stream if possible. +.It Ar host +Indicates the official name, an alias, or the Internet address +of a remote host. +.It Ar port +Indicates a port number (address of an application). +If a number is not specified, the default +.Nm +port is used. +.El +.Pp +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. +.Pp +Once a connection has been opened, +.Nm +will attempt to enable the +.Dv TELNET LINEMODE +option. +If this fails, +.Nm +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. +.Pp +When +.Dv LINEMODE +is enabled, character processing is done on the +local system, under the control of the remote system. +When input +editing or character echoing is to be disabled, the remote system +will relay that information. +The remote system will also relay +changes to any special characters that happen on the remote +system, so that they can take effect on the local system. +.Pp +In ``character at a time'' mode, most +text typed is immediately sent to the remote host for processing. +.Pp +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 character'' (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). +.Pp +If the +.Dv LINEMODE +option is enabled, or if the +.Ic localchars +toggle is +.Dv TRUE +(the default for ``old line by line''; see below), +the user's +.Ic quit , +.Ic intr , +and +.Ic flush +characters are trapped locally, and sent as +.Tn TELNET +protocol sequences to the remote side. +If +.Dv LINEMODE +has ever been enabled, then the user's +.Ic susp +and +.Ic eof +are also sent as +.Tn TELNET +protocol sequences, +and +.Ic quit +is sent as a +.Dv TELNET ABORT +instead of +.Dv BREAK . +There are options (see +.Ic toggle +.Ic autoflush +and +.Ic toggle +.Ic autosynch +below) +which cause this action to flush subsequent output to the terminal +(until the remote host acknowledges the +.Tn TELNET +sequence) and flush previous terminal input +(in the case of +.Ic quit +and +.Ic intr ) . +.Pp +While connected to a remote host, +.Nm +command mode may be entered by typing the +.Nm +``escape character'' (initially ``^]''). +When in command mode, the normal terminal editing conventions are available. +Note that the escape character will return to the command mode of the initial +invocation of +.Nm +that has the controlling terminal. +Use the +.Cm send escape +command to switch to command mode in subsequent +.Nm +processes on remote hosts. +.Pp +The following +.Nm +commands are available. +Only enough of each command to uniquely identify it need be typed +(this is also true for arguments to the +.Ic mode , +.Ic set , +.Ic toggle , +.Ic unset , +.Ic slc , +.Ic environ , +and +.Ic display +commands). +.Bl -tag -width "mode type" +.It Ic auth Ar argument Op Ar ... +The +.Ic auth +command manipulates the information sent through the +.Dv TELNET AUTHENTICATE +option. +Valid arguments for the +.Ic auth +command are as follows: +.Bl -tag -width "disable type" +.It Ic disable Ar type +Disables the specified +.Ar type +of authentication. +To obtain a list of available types, use the +.Ic auth disable \&? +command. +.It Ic enable Ar type +Enables the specified +.Ar type +of authentication. +To obtain a list of available types, use the +.Ic auth enable \&? +command. +.It Ic status +Lists the current status of the various types of +authentication. +.El +.It Ic close +Close a +.Tn TELNET +session and return to command mode. +.It Ic display Ar argument Op Ar ... +Displays all, or some, of the +.Ic set +and +.Ic toggle +values (see below). +.It Ic encrypt Ar argument Op Ar ... +The +.Ic encrypt +command manipulates the information sent through the +.Dv TELNET ENCRYPT +option. +.Pp +Valid arguments for the encrypt command are as follows: +.Bl -tag -width Ar +.It Ic disable Ar type Ic [input|output] +Disables the specified +.Ar type +of encryption. +If you omit +.Ic input +and +.Ic output , +both input and output +are disabled. +To obtain a list of available types, use the +.Ic encrypt disable \&? +command. +.It Ic enable Ar type Ic [input|output] +Enables the specified +.Ar type +of encryption. +If you omit +.Ic input +and +.Ic output , +both input and output are +enabled. +To obtain a list of available types, use the +.Ic encrypt enable \&? +command. +.It Ic input +This is the same as the +.Ic encrypt start input +command. +.It Ic -input +This is the same as the +.Ic encrypt stop input +command. +.It Ic output +This is the same as the +.Ic encrypt start output +command. +.It Ic -output +This is the same as the +.Ic encrypt stop output +command. +.It Ic start Ic [input|output] +Attempts to start encryption. +If you omit +.Ic input +and +.Ic output , +both input and output are enabled. +To obtain a list of available types, use the +.Ic encrypt enable \&? +command. +.It Ic status +Lists the current status of encryption. +.It Ic stop Ic [input|output] +Stops encryption. +If you omit +.Ic input +and +.Ic output , +encryption is on both input and output. +.It Ic type Ar type +Sets the default type of encryption to be used +with later +.Ic encrypt start +or +.Ic encrypt stop +commands. +.El +.It Ic environ Ar arguments Op Ar ... +The +.Ic environ +command is used to manipulate the +variables that may be sent through the +.Dv TELNET ENVIRON +option. +The initial set of variables is taken from the user's +environment, with only the +.Ev DISPLAY , +.Ev PRINTER , +and +.Ev XAUTHORITY +variables being exported by default. +The +.Ev USER +variable is also exported if the +.Fl a +or +.Fl l +options are used. +Additionally, the value of the +.Ev TERM +variable is by default available to be queried by the server. +.Pp +Valid arguments for the +.Ic environ +command are: +.Bl -tag -width Fl +.It Ic define Ar variable value +Define the variable +.Ar variable +to have a value of +.Ar value . +Any variables defined by this command are automatically exported. +The +.Ar value +may be enclosed in single or double quotes so +that tabs and spaces may be included. +.It Ic undefine Ar variable +Remove +.Ar variable +from the list of environment variables. +.It Ic export Ar variable +Mark the variable +.Ar variable +to be exported to the remote side. +.It Ic unexport Ar variable +Mark the variable +.Ar variable +to not be exported. +.It Ic list +List the current set of environment variables. +Those marked with a +.Cm * +will be sent automatically, +those marked with a +.Cm + +will only be sent if explicitly requested by the server, +and others won't be revealed to the server even if requested. +.It Ic \&? +Prints out help information for the +.Ic environ +command. +.El +.It Ic logout +Sends the +.Dv TELNET LOGOUT +option to the remote side. +This command is similar to a +.Ic close +command; however, if the remote side does not support the +.Dv LOGOUT +option, nothing happens. +If, however, the remote side does support the +.Dv LOGOUT +option, this command should cause the remote side to close the +.Tn TELNET +connection. +If the remote side also supports the concept of +suspending a user's session for later reattachment, +the logout argument indicates that you +should terminate the session immediately. +.It Ic mode Ar type +.Ar type +is one of several options, depending on the state of the +.Tn TELNET +session. +The remote host is asked for permission to go into the requested mode. +If the remote host is capable of entering that mode, the requested +mode will be entered. +.Bl -tag -width Ar +.It Ic character +Disable the +.Dv TELNET LINEMODE +option, or, if the remote side does not understand the +.Dv LINEMODE +option, then enter ``character at a time'' mode. +.It Ic line +Enable the +.Dv TELNET LINEMODE +option, or, if the remote side does not understand the +.Dv LINEMODE +option, then attempt to enter ``old-line-by-line'' mode. +.It Ic isig Pq Ic \-isig +Attempt to enable (disable) the +.Dv TRAPSIG +mode of the +.Dv LINEMODE +option. +This requires that the +.Dv LINEMODE +option be enabled. +.It Ic edit Pq Ic \-edit +Attempt to enable (disable) the +.Dv EDIT +mode of the +.Dv LINEMODE +option. +This requires that the +.Dv LINEMODE +option be enabled. +.It Ic softtabs Pq Ic \-softtabs +Attempt to enable (disable) the +.Dv SOFT_TAB +mode of the +.Dv LINEMODE +option. +This requires that the +.Dv LINEMODE +option be enabled. +.It Ic litecho Pq Ic \-litecho +Attempt to enable (disable) the +.Dv LIT_ECHO +mode of the +.Dv LINEMODE +option. +This requires that the +.Dv LINEMODE +option be enabled. +.It Ic \&? +Prints out help information for the +.Ic mode +command. +.El +.It Xo +.Ic open Ar host +.Op Fl l Ar user +.Oo Op Fl +.Ar port Oc +.Xc +Open a connection to the named host. +If no port number +is specified, +.Nm +will attempt to contact a +.Tn TELNET +server at the default port. +The host specification may be either a host name (see +.Xr hosts 5 ) +or an Internet address specified in the ``dot notation'' (see +.Xr inet 3 ) . +The +.Fl l +option may be used to specify the user name +to be passed to the remote system via the +.Ev ENVIRON +option. +When connecting to a non-standard port, +.Nm +omits any automatic initiation of +.Tn TELNET +options. +When the port number is preceded by a minus sign, +the initial option negotiation is done. +After establishing a connection, the file +.Pa \&.telnetrc +in the +user's home directory is opened. +Lines beginning with a ``#'' are +comment lines. +Blank lines are ignored. +Lines that begin +without whitespace 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 whitespace are assumed to be +.Nm +commands and are processed as if they had been typed +in manually to the +.Nm +command prompt. +.It Ic quit +Close any open +.Tn TELNET +session and exit +.Nm telnet . +An end-of-file (in command mode) will also close a session and exit. +.It Ic send Ar arguments +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): +.Bl -tag -width escape +.It Ic abort +Sends the +.Dv TELNET ABORT +(Abort +processes) +sequence. +.It Ic ao +Sends the +.Dv TELNET AO +(Abort Output) sequence, which should cause the remote system to flush +all output +.Em from +the remote system +.Em to +the user's terminal. +.It Ic ayt +Sends the +.Dv TELNET AYT +(Are You There) +sequence, to which the remote system may or may not choose to respond. +.It Ic brk +Sends the +.Dv TELNET BRK +(Break) sequence, which may have significance to the remote +system. +.It Ic ec +Sends the +.Dv TELNET EC +(Erase Character) +sequence, which should cause the remote system to erase the last character +entered. +.It Ic el +Sends the +.Dv TELNET EL +(Erase Line) +sequence, which should cause the remote system to erase the line currently +being entered. +.It Ic eof +Sends the +.Dv TELNET EOF +(End Of File) +sequence. +.It Ic eor +Sends the +.Dv TELNET EOR +(End of Record) +sequence. +.It Ic escape +Sends the current +.Nm +escape character (initially ``^]''). +.It Ic ga +Sends the +.Dv TELNET GA +(Go Ahead) +sequence, which likely has no significance to the remote system. +.It Ic getstatus +If the remote side supports the +.Dv TELNET STATUS +command, +.Ic getstatus +will send the subnegotiation to request that the server send +its current option status. +.It Ic ip +Sends the +.Dv TELNET IP +(Interrupt Process) sequence, which should cause the remote +system to abort the currently running process. +.It Ic nop +Sends the +.Dv TELNET NOP +(No OPeration) +sequence. +.It Ic susp +Sends the +.Dv TELNET SUSP +(SUSPend process) +sequence. +.It Ic synch +Sends the +.Dv TELNET SYNCH +sequence. +This sequence causes the remote system to discard all previously typed +(but not yet read) input. +This sequence is sent as +.Tn TCP +urgent +data (and may not work if the remote system is a +.Bx 4.2 +system -- if +it doesn't work, a lower case ``r'' may be echoed on the terminal). +.It Ic do Ar cmd +Sends the +.Dv TELNET DO +.Ar cmd +sequence. +.Ar cmd +can be either a decimal number between 0 and 255, +or a symbolic name for a specific +.Dv TELNET +command. +.Ar cmd +can also be either +.Ic help +or +.Ic \&? +to print out help information, including +a list of known symbolic names. +.It Ic dont Ar cmd +Sends the +.Dv TELNET DONT +.Ar cmd +sequence. +.Ar cmd +can be either a decimal number between 0 and 255, +or a symbolic name for a specific +.Dv TELNET +command. +.Ar cmd +can also be either +.Ic help +or +.Ic \&? +to print out help information, including +a list of known symbolic names. +.It Ic will Ar cmd +Sends the +.Dv TELNET WILL +.Ar cmd +sequence. +.Ar cmd +can be either a decimal number between 0 and 255, +or a symbolic name for a specific +.Dv TELNET +command. +.Ar cmd +can also be either +.Ic help +or +.Ic \&? +to print out help information, including +a list of known symbolic names. +.It Ic wont Ar cmd +Sends the +.Dv TELNET WONT +.Ar cmd +sequence. +.Ar cmd +can be either a decimal number between 0 and 255, +or a symbolic name for a specific +.Dv TELNET +command. +.Ar cmd +can also be either +.Ic help +or +.Ic \&? +to print out help information, including +a list of known symbolic names. +.It Ic \&? +Prints out help information for the +.Ic send +command. +.El +.It Ic set Ar argument value +.It Ic unset Ar argument value +The +.Ic set +command will set any one of a number of +.Nm +variables to a specific value or to +.Dv TRUE . +The special value +.Ic off +turns off the function associated with +the variable; this is equivalent to using the +.Ic unset +command. +The +.Ic unset +command will disable or set to +.Dv FALSE +any of the specified functions. +The values of variables may be interrogated with the +.Ic display +command. +The variables which may be set or unset, but not toggled, are +listed here. +In addition, any of the variables for the +.Ic toggle +command may be explicitly set or unset using +the +.Ic set +and +.Ic unset +commands. +.Bl -tag -width escape +.It Ic ayt +If +.Tn TELNET +is in +.Ic localchars +mode, or +.Dv LINEMODE +is enabled, and the status character is typed, a +.Dv TELNET AYT +sequence (see +.Ic send ayt +preceding) is sent to the +remote host. +The initial value for the "Are You There" +character is the terminal's status character. +.It Ic echo +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 entering, say, a password). +.It Ic eof +If +.Nm +is operating in +.Dv 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 +.Ic eof +character is taken to be the terminal's +.Ic eof +character. +.It Ic erase +If +.Nm +is in +.Ic localchars +mode (see +.Ic toggle +.Ic localchars +below), +and if +.Nm +is operating in ``character at a time'' mode, then when this +character is typed, a +.Dv TELNET EC +sequence (see +.Ic send +.Ic ec +above) +is sent to the remote system. +The initial value for the +.Ic erase +character is taken to be +the terminal's +.Ic erase +character. +.It Ic escape +This is the +.Nm +escape character (initially ``^['') which causes entry +into +.Nm +command mode (when connected to a remote system). +.It Ic flushoutput +If +.Nm +is in +.Ic localchars +mode (see +.Ic toggle +.Ic localchars +below) +and the +.Ic flushoutput +character is typed, a +.Dv TELNET AO +sequence (see +.Ic send +.Ic ao +above) +is sent to the remote host. +The initial value for the +.Ic flush +character is taken to be +the terminal's +.Ic flush +character. +.It Ic forw1 +.It Ic forw2 +If +.Tn TELNET +is operating in +.Dv 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 terminal's +eol and eol2 characters. +.It Ic interrupt +If +.Nm +is in +.Ic localchars +mode (see +.Ic toggle +.Ic localchars +below) +and the +.Ic interrupt +character is typed, a +.Dv TELNET IP +sequence (see +.Ic send +.Ic ip +above) +is sent to the remote host. +The initial value for the +.Ic interrupt +character is taken to be +the terminal's +.Ic intr +character. +.It Ic kill +If +.Nm +is in +.Ic localchars +mode (see +.Ic toggle +.Ic localchars +below), +and if +.Nm +is operating in ``character at a time'' mode, then when this +character is typed, a +.Dv TELNET EL +sequence (see +.Ic send +.Ic el +above) +is sent to the remote system. +The initial value for the +.Ic kill +character is taken to be +the terminal's +.Ic kill +character. +.It Ic lnext +If +.Nm +is operating in +.Dv LINEMODE +or ``old line by line'' mode, then this character is taken to +be the terminal's +.Ic lnext +character. +The initial value for the +.Ic lnext +character is taken to be +the terminal's +.Ic lnext +character. +.It Ic quit +If +.Nm +is in +.Ic localchars +mode (see +.Ic toggle +.Ic localchars +below) +and the +.Ic quit +character is typed, a +.Dv TELNET BRK +sequence (see +.Ic send +.Ic brk +above) +is sent to the remote host. +The initial value for the +.Ic quit +character is taken to be +the terminal's +.Ic quit +character. +.It Ic reprint +If +.Nm +is operating in +.Dv LINEMODE +or old line by line'' mode, then this character is taken to +be the terminal's +.Ic reprint +character. +The initial value for the +.Ic reprint +character is taken to be +the terminal's +.Ic reprint +character. +.It Ic rlogin +This is the rlogin escape character. +If set, the normal +.Tn 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 +.Nm +command. +The initial state is to +disable the +.Ic rlogin +escape character. +.It Ic start +If the +.Dv TELNET TOGGLE-FLOW-CONTROL +option has been enabled, +then this character is taken to +be the terminal's +.Ic start +character. +The initial value for the +.Ic start +character is taken to be +the terminal's +.Ic start +character. +.It Ic stop +If the +.Dv TELNET TOGGLE-FLOW-CONTROL +option has been enabled, +then this character is taken to +be the terminal's +.Ic stop +character. +The initial value for the +.Ic stop +character is taken to be +the terminal's +.Ic stop +character. +.It Ic susp +If +.Nm +is in +.Ic localchars +mode, or +.Dv LINEMODE +is enabled, and the +.Ic suspend +character is typed, a +.Dv TELNET SUSP +sequence (see +.Ic send +.Ic susp +above) +is sent to the remote host. +The initial value for the +.Ic suspend +character is taken to be +the terminal's +.Ic suspend +character. +.It Ic tracefile +This is the file to which the output, caused by +.Ic netdata +or +.Ic option +tracing being +.Dv TRUE , +will be written. +If it is set to +.Dq Fl , +then tracing information will be written to standard output (the default). +.It Ic worderase +If +.Nm +is operating in +.Dv LINEMODE +or ``old line by line'' mode, then this character is taken to +be the terminal's +.Ic worderase +character. +The initial value for the +.Ic worderase +character is taken to be +the terminal's +.Ic worderase +character. +.It Ic \&? +Displays the legal +.Ic set +.Pq Ic unset +commands. +.El +.It Ic skey Ar sequence challenge +The +.Ic skey +command computes a response to the S/Key challenge. +See +.Xr skey 1 +for more information on the S/Key system. +.It Ic slc Ar state +The +.Ic slc +command (Set Local Characters) is used to set +or change the state of the special +characters when the +.Dv TELNET LINEMODE +option has +been enabled. +Special characters are characters that get mapped to +.Tn TELNET +commands sequences (like +.Ic ip +or +.Ic quit ) +or line editing characters (like +.Ic erase +and +.Ic kill ) . +By default, the local special characters are exported. +.Bl -tag -width Fl +.It Ic check +Verify the current settings for the current special 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. +.It Ic export +Switch to the local defaults for the special characters. +The local default characters are those of the local terminal at +the time when +.Nm +was started. +.It Ic import +Switch to the remote defaults for the special characters. +The remote default characters are those of the remote system +at the time when the +.Tn TELNET +connection was established. +.It Ic \&? +Prints out help information for the +.Ic slc +command. +.El +.It Ic status +Show the current status of +.Nm telnet . +This includes the peer one is connected to, as well +as the current mode. +.It Ic toggle Ar arguments Op Ar ... +Toggle (between +.Dv TRUE +and +.Dv FALSE ) +various flags that control how +.Nm +responds to events. +These flags may be set explicitly to +.Dv TRUE +or +.Dv FALSE +using the +.Ic set +and +.Ic unset +commands listed above. +More than one argument may be specified. +The state of these flags may be interrogated with the +.Ic display +command. +Valid arguments are: +.Bl -tag -width Ar +.It Ic authdebug +Turns on debugging information for the authentication code. +.It Ic autoflush +If +.Ic autoflush +and +.Ic localchars +are both +.Dv TRUE , +then when the +.Ic ao +or +.Ic quit +characters are recognized (and transformed into +.Tn TELNET +sequences; see +.Ic set +above for details), +.Nm +refuses to display any data on the user's terminal +until the remote system acknowledges (via a +.Dv TELNET TIMING MARK +option) +that it has processed those +.Tn TELNET +sequences. +The initial value for this toggle is +.Dv TRUE +if the terminal user had not +done an "stty noflsh", otherwise +.Dv FALSE +(see +.Xr stty 1 ) . +.It Ic autodecrypt +When the +.Dv TELNET ENCRYPT +option is negotiated, by +default the actual encryption (decryption) of the data +stream does not start automatically. +The +.Ic autoencrypt +.Pq Ic autodecrypt +command states that encryption of the +output (input) stream should be enabled as soon as +possible. +.Pp +.It Ic autologin +If the remote side supports the +.Dv TELNET AUTHENTICATION +option +.Tn TELNET +attempts to use it to perform automatic authentication. +If the +.Dv AUTHENTICATION +option is not supported, the user's login +name are propagated through the +.Dv TELNET ENVIRON +option. +This command is the same as specifying +.Ar a +option on the +.Ic open +command. +.It Ic autosynch +If +.Ic autosynch +and +.Ic localchars +are both +.Dv TRUE , +then when either the +.Ic intr +or +.Ic quit +character is typed (see +.Ic set +above for descriptions of the +.Ic intr +and +.Ic quit +characters), the resulting +.Tn TELNET +sequence sent is followed by the +.Dv TELNET SYNCH +sequence. +This procedure +.Em should +cause the remote system to begin throwing away all previously +typed input until both of the +.Tn TELNET +sequences have been read and acted upon. +The initial value of this toggle is +.Dv FALSE . +.It Ic binary +Enable or disable the +.Dv TELNET BINARY +option on both input and output. +.It Ic inbinary +Enable or disable the +.Dv TELNET BINARY +option on input. +.It Ic outbinary +Enable or disable the +.Dv TELNET BINARY +option on output. +.It Ic crlf +If this is +.Dv TRUE , +then carriage returns will be sent as +.Li <CR><LF> . +If this is +.Dv FALSE , +then carriage returns will be send as +.Li <CR><NUL> . +The initial value for this toggle is +.Dv FALSE . +.It Ic crmod +Toggle carriage return mode. +When this mode is enabled, most carriage return characters received 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 never line feeds. +The initial value for this toggle is +.Dv FALSE . +.It Ic debug +Toggles socket level debugging (useful only to the superuser). +The initial value for this toggle is +.Dv FALSE . +.It Ic encdebug +Turns on debugging information for the encryption code. +.It Ic localchars +If this is +.Dv TRUE , +then the +.Ic flush , +.Ic interrupt , +.Ic quit , +.Ic erase , +and +.Ic kill +characters (see +.Ic set +above) are recognized locally, and transformed into (hopefully) appropriate +.Tn TELNET +control sequences +(respectively +.Ic ao , +.Ic ip , +.Ic brk , +.Ic ec , +and +.Ic el ; +see +.Ic send +above). +The initial value for this toggle is +.Dv TRUE +in ``old line by line'' mode, +and +.Dv FALSE +in ``character at a time'' mode. +When the +.Dv LINEMODE +option is enabled, the value of +.Ic localchars +is ignored, and assumed to always be +.Dv TRUE . +If +.Dv LINEMODE +has ever been enabled, then +.Ic quit +is sent as +.Ic abort , +and +.Ic eof +and +.Ic suspend +are sent as +.Ic eof +and +.Ic susp +(see +.Ic send +above). +.It Ic netdata +Toggles the display of all network data (in hexadecimal format). +The initial value for this toggle is +.Dv FALSE . +.It Ic options +Toggles the display of some internal +.Nm +protocol processing (having to do with +.Tn TELNET +options). +The initial value for this toggle is +.Dv FALSE . +.It Ic prettydump +When the +.Ic netdata +toggle is enabled, if +.Ic prettydump +is enabled the output from the +.Ic netdata +command will be formatted in a more user readable format. +Spaces are put between each character in the output, and the +beginning of any +.Tn TELNET +escape sequence is preceded by a '*' to aid in locating them. +.It Ic skiprc +When the skiprc toggle is +.Dv TRUE , +.Tn TELNET +skips the reading of the +.Pa \&.telnetrc +file in the user's home +directory when connections are opened. +The initial value for this toggle is +.Dv FALSE . +.It Ic termdata +Toggles the display of all terminal data (in hexadecimal format). +The initial value for this toggle is +.Dv FALSE . +.It Ic verbose_encrypt +When the +.Ic verbose_encrypt +toggle is +.Dv TRUE , +.Nm +prints out a message each time encryption is enabled or +disabled. +The initial value for this toggle is +.Dv FALSE . +.It Ic \&? +Displays the legal +.Ic toggle +commands. +.El +.It Ic z +Suspend +.Nm telnet . +This command only works when the user is using the +.Xr csh 1 . +.It Ic \&! Op Ar command +Execute a single command in a subshell on the local +system. +If +.Ar command +is omitted, then an interactive +subshell is invoked. +.It Ic \&? Op Ar command +Get help. +With no arguments, +.Nm +prints a help summary. +If a command is specified, +.Nm +will print the help information for just that command. +.El +.Sh ENVIRONMENT +.Nm +uses at least the +.Ev HOME , +.Ev SHELL , +.Ev DISPLAY , +and +.Ev TERM +environment variables. +Other environment variables may be propagated +to the other side via the +.Dv TELNET ENVIRON +option. +.Sh FILES +.Bl -tag -width ~/.telnetrc -compact +.It Pa ~/.telnetrc +user customized telnet startup values +.El +.Sh HISTORY +The +.Nm +command appeared in +.Bx 4.2 . +.Sh NOTES +On some remote systems, echo has to be turned off manually when in +``old line by line'' mode. +.Pp +In ``old line by line'' mode or +.Dv LINEMODE +the terminal's +.Ic eof +character is only recognized (and sent to the remote system) +when it is the first character on a line. +.Pp +Source routing is not supported yet for IPv6. |