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telnet(1)			 User Commands			     telnet(1)

NAME
       telnet -	user interface to a remote system using	the TELNET protocol

SYNOPSIS
       telnet  [-8ELcdr]  [-e escape_char] [-l user] [-n file] [ [ [!] @hop1 [
       @hop2...] @] host [port]]

DESCRIPTION
       The telnet utility communicates with another host using the TELNET pro-
       tocol.  If telnet is invoked without arguments, it enters command mode,
       indicated by its	prompt,	telnet>. In this mode, it accepts and executes
       its  associated	commands.  See USAGE, telnet Commands, below. If it is
       invoked with arguments, it performs an open command  with  those	 argu-
       ments.

       If, for example,	a host is specified as @hop1@hop2@host,	the connection
       goes through hosts hop1 and hop2, using loose source routing to end  at
       host.  If  a  leading  !	 is used, the connection follows strict	source
       routing.	Note that when telnet uses IPv6, it can	only use loose	source
       routing,	and the	connection ignores the !.

       Once  a	connection  has	been opened, telnet enters input mode. In this
       mode, text typed	is sent	to the remote host.  The  input	 mode  entered
       will  be	 either	 "line	mode",	"character at a	time", or "old line by
       line", depending	upon what the remote system supports.

       In "line	mode", character processing is done on the local system, under
       the control of the remote system. When input editing or character echo-
       ing 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.

       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.
       (Use  this  mostly  to  enter  passwords	 without  the  password	 being
       echoed.).

       If the "line mode" option is enabled, or	if the	localchars  toggle  is
       TRUE  (the  default in "old line	by line" mode),	the user's quit, intr,
       and flush characters are	trapped	locally, and sent as  TELNET  protocol
       sequences  to  the  remote  side. If "line mode"	has ever been enabled,
       then the	user's susp and	eof are	 also  sent  as	 TELNET	 protocol  se-
       quences.	 quit is then sent as a	TELNET ABORT instead of	BREAK. The op-
       tions toggle autoflush and toggle  autosynch cause this action to flush
       subsequent  output  to the terminal (until the remote host acknowledges
       the TELNET sequence); and to flush previous terminal input, in the case
       of quit and intr.

       While  connected	 to  a	remote host, the user can enter	telnet command
       mode by typing the telnet escape	character (initially ^]). When in com-
       mand  mode,  the	 normal	 terminal  editing  conventions	are available.
       Pressing	 <RETURN> at the telnet	command	prompt causes  telnet to  exit
       command mode.

OPTIONS
       The following options are supported:

	      -8    Specifies  an  8-bit data path. Negotiating	the TELNET BI-
		    NARY option	is attempted for both input and	output.

	      -c    Disables the reading of the	user's telnetrc	file. (See the
		    toggle skiprc command on this reference page.)

	      -d    Sets the initial value of the debug	toggle to TRUE.

	      -e  escape_char
		    Sets  the  initial	escape	character  to escape_char. es-
		    cape_char may also be a two	character sequence  consisting
		    of	'^' followed by	one character. If the second character
		    is '?', the	DEL character is selected. Otherwise, the sec-
		    ond	character is converted to a control character and used
		    as the escape character.  If the escape character  is  the
		    null string	(that is, -e ''), it is	disabled.

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

	      -l  user
		    When connecting to a remote	system	that  understands  the
		    ENVIRON  option, then user will be sent to the remote sys-
		    tem	as the value for the ENVIRON variable USER.

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

	      -n  tracefile
		    Opens  tracefile  for recording trace information. See the
		    set	tracefile command below.

	      -r    Specifies a	user interface	similar	 to  rlogin.  In  this
		    mode, the escape character is set to the tilde (~) charac-
		    ter, unless	modified by the	-e option. The	rlogin	escape
		    character is only recognized when it is preceded by	a car-
		    riage return. In this mode,	the  telnet escape  character,
		    normally  '^]', must still precede a  telnet command.  The
		    rlogin escape character can	also be	followed by  '.\r'  or
		    '^Z',  and,	like rlogin(1),	closes or suspends the connec-
		    tion, respectively.	This option is an  uncommitted	inter-
		    face and may change	in the future.

USAGE
   telnet Commands
       The commands described in this section are available with telnet. It is
       necessary to type only enough of	each command to	uniquely identify  it.
       (This is	also true for arguments	to the mode, set, toggle, unset, envi-
       ron, and	display	commands.)

	open [ -l user	] [ [!]	@hop1 [@ hop2 ...]@host	[  port	]
	     Open a connection to the named host. If no	port number is	speci-
	     fied,  telnet  will attempt to contact a TELNET server at the de-
	     fault port. The host specification	may be either a	host name (see
	     hosts(4),	ipnodes(4))  or	 an  Internet address specified	in the
	     "dot notation" (see inet( 7P) or inet6(  7P)).  If	 the  host  is
	     specified	as  @hop1@hop2@host, the connection goes through hosts
	     hop1 and hop2, using loose	source routing to end at host. The "@"
	     symbol is required	as a separator between the hosts specified. If
	     a leading ! is used with  IPv4,  the  connection  follows	strict
	     source routing.

	     The  -l  option passes the	user as	the value of the ENVIRON vari-
	     able USER to the remote system.

       close Close any open TELNET session and exit telnet. An EOF (in command
	     mode) will	also close a session and exit.

       quit  Same as close.

       z     Suspend  telnet. This command only	works when the user is using a
	     shell that	supports job control, such as sh(1).

       mode type
	     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. The argument type is one  of  the
	     following:

	     character
		   Disable  the	TELNET LINEMODE	option,	or, if the remote side
		   does	not understand the LINEMODE option, then enter	"char-
		   acter at a time" mode.

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

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

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

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

	     litecho (-litecho)
		   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 mode command.

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

       display
	     [ argument...] Display all, or some, of the set and toggle	values
	     (see toggle argument...).

       ?     [command ]	Get help. With no arguments, telnet prints a help sum-
	     mary.  If	a command is specified,	telnet will print the help in-
	     formation for just	that command.

       send argument ...
	     Send one or more special character	sequences to the remote	 host.
	     The  following are	the arguments that can be specified (more than
	     one argument may be specified at a	time):

	      escape
		   Send	the current telnet escape character (initially ^]).

	     synch Send	the TELNET SYNCH sequence. This	sequence discards  all
		   previously  typed,  but  not	 yet read, input on the	remote
		   system. This	sequence is sent as TCP	urgent	data  and  may
		   not	work  if  the remote system is a 4.2 BSD system. If it
		   does	not work, a lower case "r" may be echoed on the	termi-
		   nal.

	     brk or break
		   Send	 the  TELNET BRK (Break) sequence, which may have sig-
		   nificance to	the remote system.

	     ip	   Send	the TELNET  IP	(Interrupt  Process)  sequence,	 which
		   aborts the currently	running	process	on the remote system.

	     abort Send	the TELNET ABORT (Abort	Process) sequence.

	     ao	   Send	 the  TELNET AO	(Abort Output) sequence, which flushes
		   all output from the remote system to	the user's terminal.

	     ayt   Send	the TELNET AYT (Are You	There) sequence, to which  the
		   remote system may or	may not	respond.

	     ec	   Send	the TELNET EC (Erase Character)	sequence, which	erases
		   the last character entered.

	     el	   Send	the TELNET EL  (Erase  Line)  sequence,	 which	should
		   cause  the  remote system to	erase the line currently being
		   entered.

	     eof   Send	the TELNET EOF (End Of File) sequence.

	     eor   Send	the TELNET EOR (End Of Record) sequence.

	     ga	   Send	the TELNET GA (Go Ahead) sequence, which probably  has
		   no significance for the remote system.

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

	     nop   Send	the TELNET NOP (No Operation) sequence.

	     susp  Send	the TELNET SUSP	(Suspend Process) sequence.

	     do	option

	     dont option

	      will option

	     wont  option
		   Send	 the TELNET protocol option negotiation	indicated. Op-
		   tion	may be the text	name of	the protocol  option,  or  the
		   number  corresponding  to  the  option. The command will be
		   silently ignored if the option negotiation indicated	is not
		   valid  in  the  current  state.  If	the option is given as
		   'help' or '?', the list of option names  known  is  listed.
		   This	 command is mostly useful for unusual debugging	situa-
		   tions.

	     ?	   Print out help information for the send command.

       set argument [  value ]

       unset  argument
	     Set any one of a number of	telnet variables to a specific	value.
	     The  special  value  "off"	turns off the function associated with
	     the variable. The values of variables may	be  interrogated  with
	     the  display  command. If value is	omitted, the value is taken to
	     be	true, or "on".	If the unset form is used, the value is	 taken
	     to	be false, or "off." The	variables that may be specified	are:

	     echo  This	 is  the  value	 (initially ^E)	that, when in "line by
		   line" mode, toggles between local echoing of	entered	 char-
		   acters  for	normal	processing, and	suppressing echoing of
		   entered characters, for example, entering a password.

	     escape
		   This	is the telnet escape character (initially ^]) that en-
		   ters	  telnet  command mode when connected to a remote sys-
		   tem.

	     interrupt
		   If telnet is	in localchars mode  (see  toggle,  localchars)
		   and	the interrupt character	is typed, a TELNET IP sequence
		   (see	send and ip) is	sent to	the remote host.  The  initial
		   value for the interrupt character is	taken to be the	termi-
		   nal's intr character.

	     quit  If telnet is	in localchars mode and the quit	 character  is
		   typed, a TELNET BRK sequence	(see send, brk)	is sent	to the
		   remote host.	The initial value for the  quit	 character  is
		   taken to be the terminal's quit character.

	     flushoutput
		   If telnet is	in localchars mode and the flushoutput charac-
		   ter is typed, a TELNET AO sequence (see send, ao)  is  sent
		   to  the remote host.	The initial value for the  flush char-
		   acter is taken to be	the terminal's flush character.

	     erase If telnet is	in localchars mode and operating in "character
		   at  a time" mode, then when the erase character is typed, a
		   TELNET EC sequence (see send, ec) is	 sent  to  the	remote
		   system. The initial value for the  erase character is taken
		   to be the terminal's	erase character.

	     kill  If telnet is	in localchars mode and operating in "character
		   at  a  time"	mode, then when	the kill character is typed, a
		   TELNET EL sequence (see send, el) is	 sent  to  the	remote
		   system.  The	initial	value for the  kill character is taken
		   to be the terminal's	kill character.

	     eof   If telnet is	operating in "line by line" mode, entering the
		   eof	character as the first character on a line  sends this
		   character to	the remote system. The initial value  of   eof
		   is taken to be the terminal's eof character.

	     ayt   If  telnet  is in  localchars mode, or LINEMODE is enabled,
		   and the status character is typed, a	TELNET AYT  ("Are  You
		   There") sequence is sent to the remote host.	(See send, ayt
		   above.) The initial value for ayt is	the terminal's	status
		   character.

	     forw1

	     forw2 If  telnet is operating in LINEMODE,	and the	forw1 or forw2
		   characters are typed, this causes the forwarding of partial
		   lines to the	remote system. The initial values for the for-
		   warding characters come from	the terminal's eol  and	  eol2
		   characters.

	     lnext If  telnet  is  operating in	LINEMODE or "old line by line"
		   mode, then the lnext	character is assumed to	be the	termi-
		   nal's  lnext	 character.  The  initial value	for the	 lnext
		   character is	taken to be the	terminal's lnext character.

	     reprint
		   If telnet is	operating in LINEMODE or "old  line  by	 line"
		   mode,  then the reprint character is	assumed	to be the ter-
		   minal's reprint character. The initial value	 for   reprint
		   is taken to be the terminal's reprint character.

	     rlogin
		   This	 is  the   rlogin escape character. If set, the	normal
		   telnet escape character is ignored, unless it  is  preceded
		   by  this  character	at the beginning of a line. The	rlogin
		   character, at the beginning of a line  followed  by	a  "."
		   closes  the	connection. When followed by a	^Z, the	rlogin
		   command suspends the	 telnet	command.  The initial state is
		   to disable the rlogin escape	character.

	     start If  the TELNET TOGGLE-FLOW-CONTROL option has been enabled,
		   then	the start character is	taken  to  be  the  terminal's
		   start  character. The initial value for the	kill character
		   is taken to be the terminal's start character.

	     stop  If the TELNET TOGGLE-FLOW-CONTROL option has	been  enabled,
		   then	 the stop character is taken to	be the terminal's stop
		   character. The initial value	 for  the  kill	 character  is
		   taken to be the terminal's stop character.

	     susp  If  telnet  is  in localchars mode, or LINEMODE is enabled,
		   and the suspend character is	typed, a TELNET	SUSP  sequence
		   (see	 send,	susp  above)  is sent to the remote host.  The
		   initial value for the suspend character is taken to be  the
		   terminal's suspend character.

	     tracefile
		   This	 is  the  file to which	the output, generated when the
		   netdata or the debug	option is TRUE,	will  be  written.  If
		   tracefile  is  set to "-", then tracing information will be
		   written to standard output (the default).

	     worderase
		   If telnet is	operating in LINEMODE or "old  line  by	 line"
		   mode,  then	this  character	 is taken to be	the terminal's
		   worderase character.	The initial value for  the   worderase
		   character  is  taken	to be the terminal's worderase charac-
		   ter.

	     ?	   Displays the	legal set and unset commands.

       slc state
	     The slc (Set Local	Characters) command is used to set  or	change
	     the  state	 of special characters when the	TELNET LINEMODE	option
	     has been enabled. Special	characters  are	 characters  that  get
	     mapped  to	 TELNET	 commands  sequences (like ip or quit) or line
	     editing characters	(like erase and	kill). By default,  the	 local
	     special  characters are exported.	The following values for state
	     are valid:

	      check
		    Verifies the settings for the current special  characters.
		   The	remote	side is	requested to send all the current spe-
		   cial	character settings. If	there  are  any	 discrepancies
		   with	 the local side, the local settings will switch	to the
		   remote values.

	     export
		   Switches to the local defaults for the special  characters.
		   The	local default characters are those of the local	termi-
		   nal at the time when	telnet was started.

	     import
		   Switches to the remote defaults for the special characters.
		   The	remote default characters are those of the remote sys-
		   tem at the time when	the TELNET connection was established.

	     ?	   Prints out help information for the slc command.

       toggle argument ...
	     Toggle between TRUE and FALSE the various flags that control  how
	     telnet  responds  to events. More than one	argument may be	speci-
	     fied. The state of	these flags may	be interrogated	with the  dis-
	     play command. Valid arguments are:

	     autoflush
		   If  autoflush  and  localchars are both TRUE, then when the
		   ao, intr, or	 quit characters are  recognized  (and	trans-
		   formed  into	TELNET sequences; see set for details),	telnet
		   refuses to display any data on the  user's  terminal	 until
		   the	remote system acknowledges (using a TELNET Timing Mark
		   option) that	it has processed those TELNET  sequences.  The
		   initial  value for this toggle is TRUE if the terminal user
		   has not done	an "stty  noflsh".  Otherwise,	the  value  is
		   FALSE (see stty(1)).

	     autosynch
		   If autosynch	and localchars are both	TRUE, then when	either
		   the interrupt or quit characters are	typed (see set for de-
		   scriptions of interrupt and quit), the resulting TELNET se-
		   quence sent is followed by the TELNET SYNCH sequence.  This
		   procedure  should 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.

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

	     inbinary
		   Enable or disable the TELNET	BINARY option on input.

	     outbinary
		   Enable or disable the TELNET	BINARY option on output.

	     crlf  Determines  how  carriage returns are sent. If the value is
		   TRUE, then carriage returns will be sent  as	 <CR><LF>.  If
		   the	value  is FALSE, then carriage returns will be send as
		   <CR><NUL>.  The initial value for this toggle is FALSE.

	     crmod Toggle
		    <RETURN> mode. When	this mode is  enabled,	most  <RETURN>
		   characters  received	 from  the  remote host	will be	mapped
		   into	a  <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 useful only for
		   remote  hosts that send <RETURN> but	never send <LINEFEED>.
		   The initial value for this toggle is	FALSE.

	     debug Toggle socket level debugging (only available to the	super-
		   user). The initial value for	this toggle is FALSE.

	     localchars
		   If  this  toggle  is	TRUE, then the flush, interrupt, quit,
		   erase, and kill characters (see  set)  are  recognized  lo-
		   cally,  and transformed into	appropriate TELNET control se-
		   quences, respectively ao, ip, brk, ec, and el  (see	send).
		   The initial value for this toggle is	TRUE in	"line by line"
		   mode, and FALSE in "character at a  time"  mode.  When  the
		   LINEMODE  option is enabled,	the value of localchars	is ig-
		   nored, and assumed always to	be TRUE. If LINEMODE has  ever
		   been	 enabled, then quit is sent as abort, and eof and sus-
		   pend	are sent as eof	and susp (see send above).

	     netdata
		   Toggle the display of all network data (in hexadecimal for-
		   mat). The initial value for this toggle is FALSE.

	     options
		   Toggle  the	display	 of some internal TELNET protocol pro-
		   cessing (having to do with  telnet  options).  The  initial
		   value for this toggle is FALSE.

	     prettydump
		   When	 the  netdata  toggle is enabled, if prettydump	is en-
		   abled, the output from the netdata command will be  format-
		   ted	in a more user readable	format.	Spaces are put between
		   each	character in the output.  The beginning	of any	TELNET
		   escape  sequence  is	 preceded by an	asterisk (*) to	aid in
		   locating them.

	     skiprc
		   When	the  skiprc toggle is TRUE, TELNET skips  the  reading
		   of  the  .telnetrc  file  in	the user's home	directory when
		   connections are opened. The initial value for  this	toggle
		   is FALSE.

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

	     ?	   Display the legal toggle commands.

       environ argument...
	     The environ command is used to manipulate variables that  may  be
	     sent  through the TELNET ENVIRON option. The initial set of vari-
	     ables is taken from the users environment.	Only the  DISPLAY  and
	     PRINTER  variables	 are  exported by default. Valid arguments for
	     the environ command are:

	     define variable value
		   Define variable to have a value of value. Any variables de-
		   fined by this command are automatically exported. The value
		   may be enclosed in single or	double quotes,	so  that  tabs
		   and spaces may be included.

	     undefine variable
		   Remove variable from	the list of environment	variables.

	     export variable
		   Mark	the variable to	be exported to the remote side.

	     unexport variable
		   Mark	the  variable to not be	exported unless	explicitly re-
		   quested by the remote side.

	     list  List	the current set	of environment variables. Those	marked
		   with	 an  asterisk  (*)  will  be sent automatically. Other
		   variables will be sent only if explicitly requested.

	     ?	   Prints out help information for the environ command.

       logout
	     Sends the telnet logout option to the remote side.	 This  command
	     is	 similar  to a close 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 connection. If the  re-
	     mote  side	 also supports the concept of suspending a user's ses-
	     sion for later reattachment, the  logout argument indicates  that
	     the remote	side should terminate the session immediately.

FILES
	$HOME/.telnetrc
	     file  that	 contains  commands to be executed before initiating a
	     telnet session

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWtnetc			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       rlogin(1),  sh(1),  stty(1),  hosts(4),	ipnodes(4),  nologin(4),  tel-
       netrc(4), attributes(5),	inet(7P), inet6(7P)

DIAGNOSTICS
	NO LOGINS: System going	down in	N  minutes
	     The  machine is in	the process of being shut down and logins have
	     been disabled.

NOTES
       On some remote systems, echo has	to be  turned  off  manually  when  in
       "line by	line" mode.

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

SunOS 5.9			  6 Nov	2000			     telnet(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | USAGE | FILES | ATTRIBUTES | SEE ALSO | DIAGNOSTICS | NOTES

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