telnetd(1M)                      (TCP/IP)                       telnetd(1M)


   NAME
         telnetd - DARPA TELNET protocol server

   SYNOPSIS
         in.telnetd

   DESCRIPTION
         telnetd is a server which supports the DARPA standard TELNET virtual
         terminal protocol.  telnetd is invoked by the internet server [see
         inetd(1M)], normally for requests to connect to the TELNET port as
         indicated by the /etc/services file [see services(4)].

         telnetd operates by allocating a pseudo-terminal device for a client,
         then creating a login process which has the slave side of the
         pseudo-terminal as its standard input, output, and error.  telnetd
         manipulates the master side of the pseudo-terminal, implementing the
         TELNET protocol and passing characters between the remote client and
         the login process.

         When a TELNET session is started up, telnetd sends TELNET options to
         the client side indicating a willingness to do remote echo of
         characters, to suppress go ahead, and to receive terminal type
         information from the remote client.  If the remote client is willing,
         the remote terminal type is propagated in the environment of the
         created login process.  The pseudo-terminal allocated to the client
         is configured to operate in cooked mode, and with XTABS, ICRNL, and
         ONLCR enabled [see termio(4)].

         telnetd is willing to do:  echo, binary, suppress go ahead, and
         timing mark.  telnetd is willing to have the remote client do:
         binary, terminal type, and suppress go ahead.

   SEE ALSO
         telnet(1)

         Postel, Jon, and Joyce Reynolds, ``Telnet Protocol Specification,''
         RFC 854, Network Information Center, SRI International, Menlo Park,
         Calif., May 1983.

   NOTES
         Some TELNET commands are only partially implemented.

         The TELNET protocol allows for the exchange of the number of lines
         and columns on the user's terminal, but telnetd doesn't make use of
         them.

         Binary mode has no common interpretation except between similar
         operating systems





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   telnetd(1M)                      (TCP/IP)                       telnetd(1M)


         The terminal type name received from the remote client is converted
         to lower case.

         The packet interface to the pseudo-terminal should be used for more
         intelligent flushing of input and output queues.

         telnetd never sends TELNET go ahead commands.

         telnetd can only support 64 pseudo-terminals.












































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