telnetd(8)						      System Manager's Manual							telnetd(8)

NAME

       telnetd - The DARPA telnet protocol server

SYNOPSIS

       telnetd [-debug [port]] [-D modifier ...]

FLAGS

       Starts  telnetd	manually,  rather than through inetd, on alternate TCP port number port (if specified).  Prints out debugging information.
       modifiers are: Prints information about negotiation of telnet options Same as options with additional processing information  Displays  the
       data stream received by telnetd Displays data written to the pty Not yet implemented

DESCRIPTION

       The  telnetd daemon is a server that supports the DARPA (Defense Advanced Research Projects Agency) standard telnet virtual terminal proto-
       col.  telnetd is invoked by the Internet server (see inetd(8)) normally for requests to connect to the telnet  port  as	indicated  by  the
       /etc/services  file  (see  services(4)).   The  -debug flag may be used, to start up telnetd manually.  If started up this way, port may be
       specified to run telnetd on an alternate TCP port number.

       The -D options may be used for debugging purposes.  This allows telnetd to print out debugging information to the connection, allowing  the
       user to see what telnetd is doing.

       The  telnetd  daemon  operates  by allocating a pseudoterminal device (see pty(7)) for a client, then creating a login process 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 charac-
       ters, to suppress go ahead, to do remote flow control, and to receive terminal type information, terminal  speed  information,  and  window
       size 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 pseudoterminal allocated to the client is configured to operate in  cooked  mode,  and  with  XTABS	and  CRMOD
       enabled (see tty(7)).

       The  telnetd  daemon  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 daemon 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.

       The telnet command uses the default Type-of-Service value recommended by RFC1060, which is as follows: Low delay

       You can configure this value by specifying it in the /etc/iptos file. For more information, see iptos(4).

       By default, the telnetd daemon starts the login dialog using the login string specified in the message field of	the  /etc/gettydefs  file.
       If  you	want  to  use  a customized banner, create an /etc/issue.net or /etc/issue file. The telnetd daemon reads the file that exists and
       writes its contents over a new telnet connection prior to starting the login dialog. If both files exist, only the /etc/issue.net  file	is
       used.

CAUTIONS

       Some telnet commands are only partially implemented.

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

FILES

       Specifies the command path.  Specifies the path name for the network issue identification file.	Specifies the  path  name  for	the  issue
       identification file.

RELATED INFORMATION

       Commands: telnet(1).

       Files: iptos(4), issue(4), issue.net(4).  delim off

																	telnetd(8)