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telnet(1)				  User Commands 				telnet(1)

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

SYNOPSIS
       telnet [-8EFKLacdfrx] [-X atype] [-e escape_char]
	    [-k realm] [-l user] [-n file]
	    [ [ [!] @hop1 [@hop2...] @] host [port]]

DESCRIPTION
       The  telnet utility communicates with another host using the TELNET protocol. 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. If it is invoked
       with arguments, it performs an open command with those arguments.

       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 con-
       nection follows strict source routing. Notice 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 echoing is to be disabled, the remote  sys-
       tem  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 character" (initially ^E) may be used
       to turn off and on the local echo. (Use this mostly to enter passwords without  the  pass-
       word 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 sequences. quit  is
       then  sent  as  a  TELNET  ABORT instead of BREAK. The options 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 command 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 BINARY option is attempted for
	   both input and output.

       -a

	   Attempts automatic login. This sends the user name by means of the  USER  variable  of
	   the	ENVIRON  option,  if supported by the remote system. The name used is that of the
	   current user as returned by getlogin(3C) if it agrees with the current user ID. Other-
	   wise, it is the name associated with the user ID.

       -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. escape_char may also be a two  char-
	   acter  sequence consisting of ^ (Control key) followed by one character. If the second
	   character is ?, the DEL character is selected. Otherwise, the second character is con-
	   verted  to  a  control  character  and used as the escape character. If escape_char is
	   defined as the null string (that is, -e ''), this  is  equivalent  to  -e  '^@'  (Con-
	   trol-@). To specify that no character can be the escape character, use the -E option.

       -E

	   Stops any character from being recognized as an escape character.

       -f

	   Forwards a copy of the local credentials to the remote system.

       -F

	   Forwards a forwardable copy of the local credentials to the remote system.

       -k realm

	   If  Kerberos authentication is being used, requests that telnet obtain tickets for the
	   remote host in realm  instead  of  the  remote  host's  default  realm  as  determined
	   inkrb5.conf(4).

       -K

	   Specifies no automatic login to the remote system.

       -l user

	   When connecting to a remote system that understands the ENVIRON option, then user will
	   be sent to the remote system 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 (~) character, unless modified by the -e option.  The  rlogin  escape
	   character  is  only recognized when it is preceded by a carriage 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 connection, respectively. This option is an uncommitted  inter-
	   face and may change in the future.

       -x

	   Turns  on  encryption  of  the data stream. When this option is turned on, telnet will
	   exit with an error if authentication cannot be negotiated or if encryption  cannot  be
	   turned on.

       -X atype

	   Disables the atype type of authentication.

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, environ, and display commands.)

       auth argument ...

	   The	auth  command  manipulates  the  information sent through the TELNET AUTHENTICATE
	   option. Valid arguments for the auth command are as follows:

	   disable type

	       Disables the specified type of authentication.  To  obtain  a  list  of	available
	       types, use the auth disable ? command.

	   enable type

	       Enables the specified type of authentication. To obtain a list of available types,
	       use the auth enable ? command.

	   status

	       Lists the current status of the various types of authentication.

       open [-l user ] [ [!] @hop1 [@hop2 ...]@host [ port ]

	   Open a connection to the named host. If no  port  number  is  specified,  telnet  will
	   attempt  to contact a TELNET server at the default port. The host specification may be
	   either a host name (see hosts(4)) or an Internet address specified in the  "dot  nota-
	   tion"  (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 lead-
	   ing ! is used with IPv4, the connection follows strict source routing.

	   The -l option passes the user as the value of the ENVIRON variable 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.

       encrypt

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

	   Valid arguments for the encrypt command are as follows:

	   disable type [input|output]

	       Disables  the specified type of encryption. If you omit the input and output, both
	       input and output are disabled. To obtain  a  list  of  available  types,  use  the
	       encrypt disable ? command.

	   enable type [input|output]

	       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  encrypt
	       enable ? command.

	   input

	       This is the same as the encrypt start input command.

	   -input

	       This is the same as the encrypt stop input command.

	   output

	       This is the same as the encrypt start output command.

	   -output

	       This is the same as the encrypt stop output command.

	   start [input|output]

	       Attempts  to start encryption. If you omit input and output, both input and output
	       are enabled. To obtain a list of available types, use the encrypt  enable  ?  com-
	       mand.

	   status

	       Lists the current status of encryption.

	   stop [input|output]

	       Stops  encryption.  If  you omit input and output, encryption is on both input and
	       output.

	   type type

	       Sets the default type of encryption to be used with later encrypt start or encrypt
	       stop commands.

       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 argu-
	   ment 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 "character 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 argu-
	   ment...).

       ?

	   [command] Get help. With no arguments, telnet prints a help summary. If a  command  is
	   specified, telnet will print the help information 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
	       lowercase "r" may be echoed on the terminal.

	   brk or break

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

	   ip

	       Send the TELNET IP (Interrupt Process) sequence, which aborts the  currently  run-
	       ning 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,  getstatus  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. Option 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 situations.

	   ?

	       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 characters for normal processing, and suppressing
	       echoing of entered characters, for example, entering a password.

	   escape

	       This is the telnet escape character (initially ^]) that enters telnet command mode
	       when connected to a remote system.

	   interrupt

	       If telnet is in localchars mode (see toggle, localchars) and the interrupt charac-
	       ter  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  terminal'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 character is typed, a TELNET
	       AO sequence (see send, ao) is sent to the remote host. The initial value  for  the
	       flush character 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 val-
	       ues  for  the  forwarding characters come from the terminal's eol and eol2 charac-
	       ters.

	   lnext

	       If telnet is operating in LINEMODE or "old line by  line"  mode,  then  the  lnext
	       character  is  assumed to be the terminal'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 terminal'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  connec-
	       tion.  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  charac-
	       ter  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 char-
	       acter 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 informa-
	       tion 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 character.

	   ?

	       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 special 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 char-
	       acters are those of the local terminal 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 system 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 specified. The  state	of  these  flags  may  be
	   interrogated with the display command. Valid arguments are:

	   authdebug	       Turns on debugging information for the authentication code.

	   autodecrypt	       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.

	   autologin	       If the remote side supports the TELNET AUTHENTICATION option, tel-
			       net attempts to use it to perform automatic authentication. If the
			       AUTHENTICATION  option  is not supported, the user's login name is
			       propagated through the TELNET ENVIRON option. This command is  the
			       same as specifying the -a option on the open command.

	   autoflush	       If autoflush and localchars are both TRUE, then when the ao, intr,
			       or quit characters are recognized  (and	transformed  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 descriptions
			       of interrupt and quit), the resulting TELNET sequence sent is fol-
			       lowed  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  out-
			       put.

	   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 ini-
			       tial value for this toggle is FALSE.

	   crmod	       Toggle RETURN mode. When this mode is enabled, most RETURN charac-
			       ters  received  from  the remote host will be mapped into a RETURN
			       followed by a line feed. This mode does not affect  those  charac-
			       ters  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.

	   encdebug	       Turns on debugging information for the encryption code.

	   localchars	       If this toggle is TRUE, then the flush,	interrupt,  quit,  erase,
			       and  kill  characters (see set) are recognized locally, and trans-
			       formed into appropriate TELNET control sequences, 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 ignored, and assumed always to be TRUE. If  LINEMODE	has  ever
			       been  enabled, then quit is sent as abort, and eof and suspend are
			       sent as eof and susp (see send above).

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

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

	   prettydump	       When  the netdata toggle is enabled, if prettydump is enabled, the
			       output from the netdata command will be formatted in a  more  user
			       readable format. Spaces are put between each character in the out-
			       put. 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.

	   verbose_encrypt     When the verbose_encrypt flag is TRUE, TELNET prints out a message
			       each time encryption is enabled or disabled. 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  TEL-
	   NET	ENVIRON option. The initial set of variables 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 defined 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 requested 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 hap-
	   pens. If, however, the remote side does support the logout option, this command should
	   cause the remote side to close the TELNET connection. If the remote side also supports
	   the concept of suspending a user's session 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), getlogin(3C), hosts(4), krb5.conf(4), nologin(4),  telnetrc(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.

       The telnet protocol only uses single DES for session protection--clients  request  service
       tickets	with single DES session keys. The KDC must know that host service principals that
       offer the telnet service support single DES, which, in practice, means that  such  princi-
       pals must have single DES keys in the KDC database.

SunOS 5.11				   17 Aug 2006					telnet(1)
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