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

SYNOPSIS
     telnet [ host [ port ] ]

AVAILABILITY
     This command  is  available  with  the  Networking  software
     installation  option.   Refer  to  Installing  SunOS 4.1 for
     information on how to install optional software.

DESCRIPTION
     telnet 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 the commands listed below.  If
     it is invoked with arguments, it performs  an  open  command
     (see below) with those arguments.

     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 "character at a  time"  or
     "line by line" depending on what the remote system supports.

     In "character at a time" mode, most text  typed  is  immedi-
     ately sent to the remote host for processing.

     In "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).

     In either mode,  if  the  localchars  toggle  is  TRUE  (the
     default in line mode; see below), the user's quit, intr, and
     flush characters are trapped locally,  and  sent  as  TELNET
     protocol  sequences  to  the remote side.  There are options
     (see toggle autoflush  and  toggle  autosynch  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 quit and
     intr).

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

USAGE
  Telnet Commands

     The following commands are available.  Only enough  of  each
     command  to uniquely identify it need be typed (this is also
     true for arguments to the mode,  set,  toggle,  and  display
     commands).

     open 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(5)) or an Internet
          address specified in the "dot notation" (see inet(3N)).

     close
          Close a TELNET session and return to command mode.

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

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

     mode type
          type is either line (for "line by line" mode) or  char-
          acter  (for  "character  at  a time" mode).  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.

     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
          below).

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

     send arguments
          Send 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):

          escape
               Send the current  telnet  escape  character  (ini-
               tially `^]').

          synch
               Send 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 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
               terminal).

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

          ip   Send the TELNET IP (Interrupt  Process)  sequence,
               which  should cause the remote system to abort the
               currently running process.

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

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

          ec   Sends the TELNET EC  (Erase  Character)  sequence,
               which  should cause the remote system to erase the
               last character entered.

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

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

          nop  Sends the TELNET NOP (No Operation) sequence.

          ?    Prints out help information for the send command.

     set argument value
          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.
          The variables which may be specified are:

          echo This is the value (initially `^E') which, when  in
               "line  by  line" mode, toggles between doing local
               echoing of entered characters (for normal process-
               ing),  and  suppressing echoing of entered charac-
               ters (for entering, say, a password).

          escape
               This is the  telnet  escape  character  (initially
               `^[')  which causes entry into telnet command mode
               (when connected to a remote system).

          interrupt
               If telnet is in localchars mode (see toggle local-
               chars below) and the interrupt character is typed,
               a TELNET IP sequence (see send ip above)  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 (see toggle local-
               chars  below)  and  the quit character is typed, a
               TELNET BRK sequence (see send brk above)  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 (see toggle local-
               chars  below)  and  the  flushoutput  character is
               typed, a TELNET AO sequence (see send ao above) 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 (see toggle local-
               chars below), and if telnet is operating in "char-
               acter at a time" mode, then when this character is
               typed, a TELNET EC sequence (see send ec above) 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 (see toggle local-
               chars below), and if telnet is operating in "char-
               acter at a time" mode, then when this character is
               typed, a TELNET EL sequence (see send el above) 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  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 char-
               acter is taken to be the terminal's eof character.

     toggle arguments...
          Toggle (between TRUE and FALSE) various flags that con-
          trol  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:

          localchars
               If this is TRUE, then the flush, interrupt,  quit,
               erase,  and  kill  characters  (see set above) are
               recognized locally, and  transformed  into  (hope-
               fully)   appropriate   TELNET   control  sequences
               (respectively ao, ip, brk, ec, and  el;  see  send
               above).  The initial value for this toggle is TRUE
               in "line by line" mode, and FALSE in "character at
               a time" mode.

          autoflush
               If autoflush and localchars are  both  TRUE,  then
               when  the  ao, intr, or quit characters are recog-
               nized (and transformed into TELNET sequences;  see
               set  above for details), telnet 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
               sequences.   The  initial value for this toggle is
               TRUE if the terminal user had not  done  an  "stty
               noflsh", otherwise FALSE (see stty(1V)).

          autosynch
               If autosynch and localchars are  both  TRUE,  then
               when  either  the intr or quit characters is typed
               (see set above for descriptions of  the  intr  and
               quit  characters),  the  resulting TELNET sequence
               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.

          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
               LINEFEED.  This mode does not affect those charac-
               ters typed by the user, only those  received  from
               the  remote  host.   This  mode is not very useful
               unless the remote  host  only  sends  RETURN,  but
               never  LINEFEED. The initial value for this toggle
               is FALSE.

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

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

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

          ?    Display the legal toggle commands.

SEE ALSO
     csh(1), rlogin(1C), stty(1V) inet(3N), hosts(5)

BUGS
     There is no adequate way for dealing with flow control.

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

     There is enough settable state to justify a .telnetrc file.

     No capability for a .telnetrc file is provided.

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