NAME
	  telnetd - The	DARPA TELNET protocol server

     SYNOPSIS
	  /usr/sbin/telnetd [-debug [port]] [-l] [-D options] [-D
	  report] [-D exercise]	[-D netdata] [-D ptydata]

     DESCRIPTION
	  The telnetd daemon is	a server that supports the DARPA
	  (Defense Advanced Research Projects Agency) standard TELNET
	  virtual terminal protocol.  telnetd is invoked by the	Inter-
	  net server (see inetd(8)) normally for requests to connect
	  to the TELNET	port as	indicated by the /etc/services file
	  (see services(5)).  The -debug may be	used, to start up tel-
	  netd manually, instead of through inetd(8).  If started up
	  this way, port may be	specified to run telnetd on an alter-
	  nate TCP port	number.

	  The -D options may be	used for debugging purposes.  This
	  allows telnet	to print out debugging information to the con-
	  nection, allowing the	user to	see what telnetd is doing.
	  There	are several modifiers: options prints information
	  about	the negotiation	of TELNET options, report prints the
	  options information, plus some additional information	about
	  what processing is going on, netdata displays	the data
	  stream received by telnetd, ptydata displays data written to
	  the pty, and exercise	has not	been implemented yet.

	  The telnetd deamon operates by allocating a pseudoterminal
	  device (see pty(4)) for a client, then creating a login pro-
	  cess that has	the slave side of the pseudoterminal as	stdin,
	  stdout, and stderr.  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 , to do
	  remote flow control, and to receive terminal type informa-
	  tion , terminal speed	information , and window size informa-
	  tion from the	remote client.	If the remote client is	wil-
	  ling,	the remote terminal type is propagated in the environ-
	  ment of the created login process.  The pseudoterminal allo-
	  cated	to the client is configured to operate in "cooked"
	  mode,	and with XTABS and CRMOD enabled (see tty(4)).

	  The telnetd doamon is	willing	to do :	echo , binary ,
	  suppress go ahead , and timing mark.	Telnetd	is willing to
	  have the remote client do : line mode	, binary , terminal
	  type , terminal speed	, window size ,	toggle flow control ,
	  environment ,	X display location , and suppress go ahead .
	  The telnetd deamon never sends TELNET	go ahead commands.

	  Note that binary mode	has no common interpretation except
	  between similar operating systems (Unix compatible systems
	  in this case).

	  Note also that the terminal type name	received from the
	  remote client	is converted to	lowercase.

     CAUTION
	  Some Telnet commands are only	partially implemented.

	  Because of bugs in the original 4.2BSD telnet(1), telnetd
	  performs some	dubious	protocal exchanges to try to discover
	  if the remote	client is, in fact, a 4.2BSD telnet (1).

     FILES
	  /usr/sbin/telnetd
	       Specifies the command path

     RELATED INFORMATION
	  telnet (1)