.\"
.\" $Id: vchatd.8,v 1.2 2001/03/19 14:54:05 mickey Exp $
.\"
.Dd $Date: 2001/03/19 14:54:05 $
.Dt VCHATD 8
.Os
.Sh NAME
.Nm vchatd
.Nd telnet gateway to the VChat interactive TCP/IP chat system.
.Sh SYNOPSIS
.Nm vchatd
.Op Fl b Ar bannerfile
.Op Fl c Ar channel
.Op Fl l
.Op Fl p Ar port
.Op Fl s Ar host
.Sh DESCRIPTION
.Nm Vchatd
is a full-featured user frontend to the VChat interactive conference
system. It comes with the same functionality as
.Xr vchat 1
, but interacts as a gateway to a remote DARPA TELNET session.
.Nm Vchatd
is intended to be invoked by the
.Xr inetd 8
super-server for incoming requests on the tcp port specified by the
.Pa /etc/services
file (normally port 1170).
.Pp
.Nm Vchatd
uses the TELNET option negotiation mechanism to get informed about
the users terminal-type and screen size. If it was unable to detect
the user's terminal type (i.e. when the user's telnet client does not
support these TELNET options) it falls back to the default value
assigned at compile-time.
.Pp
It then looks up the local
.Xr termcap 5
database for the negotiated terminal type and checks the entry
for the appearance of all mandatory terminal capabilities, aborting
with an appropriate error message, if any of these capabilities is missing.
(See
.Xr vchat 1
for a description of mandatory and optional terminal characteristics).
If an appropriate termcap entry could not be found in the database,
.Nm vchatd
falls back to the default value assigned at compile-time.
.Pp
Once the TELNET option negotiation has completed,
.Nm vchatd
greets the user on ther other side with a welcome message, which
defaults to a compiled-in message, unless otherwise specified by the
.Fl b Ar bannerfile
commandline option, and prompts the user to enter a
.Nm nickname.
(See
.Xr vchat 1
for a description of
.Nm nickname
conventions).
.Pp
.Nm Vchatd
neither uses a
.Nm .vchatrc
file, nor does it mention settings in the environment as
.Xr vchat 1
does, since they would not make sense in this application context.
.Pp
See
.Xr vchat 1
for a general description of the VChat user frontend.
.Sh OPTIONS
The recognized options are as follows:
.Bl -tag -width "-lnum"
.It Fl b Ar bannerfile
This option specifies the full path to a bannerfile, which is presented
to the other side of the telnet connection upon startup.
.It Fl c Ar channel
Specifies the initial conference channel to use when connected to the
conference server.
.Pp
NOTE: This option will not be recognized by vchat conference
      servers of version 2.36m or below.
.It Fl l
Turn on logging via LOG_LOCAL2 of syslog.
.It Fl p Ar port
Use alternate tcp portnumber
.Ar port
to connect remote vchat-server.
.It Fl s Ar host
Server host to connect to.
.El
.Sh TELNET OPTION NEGOTIATION
Upon startup of a TELNET session
.Nm vchatd
sends TELNET options to the remote side, indicating a willingness to
do the following TELNET options:
.Bd -literal -offset indent
DO TERMINAL TYPE
DO NAWS
WILL SUPPRESS GO AHEAD
DO BINARY
WILL ECHO
.Ed
.Sh TELNET COMMANDS
The following TELNET commands are recognized by
.Nm vchatd:
.Bd -literal -offset indent
AYT   - Are you there?
.Ed
.Pp
.Nm vchatd
responds to this command by sending the string ``I am still alive''.
.Bd -literal -offset indent
AO    - Abort output.
.Ed
.Pp
All buffered output that has not already been output is purged.
(This currently applies only to the FreeBSD version).
.Bd -literal -offset indent
IP    - Interrupt process!
.Ed
.Pp
The vchatd process is terminated upon receipt of this signal.
.Sh WINDOW RESIZING
Dynamic window resizing is supported by the use of the TELNET NAWS option.
Each time
.Nm vchatd
receives a TELNET NAWS subnegotiation sequence, it clears the conference-window
and resizes the screen to the appropriate size.
.Pp
This option is available only, if the remote telnet client has signaled it's
willingness to use the TELNET NAWS option during initial option negotiation.
.Sh SEE ALSO
.Xr inetd.conf 5 ,
.Xr services 5 ,
.Xr termcap 5 ,
.Xr vserver 8 ,
.Xr vchatctl 8 ,
.Xr vchat 1
.Sh STANDARDS
.Bl -tag -compact -width RFC-1572
.It Cm RFC-854
.Tn TELNET
PROTOCOL SPECIFICATION
.It Cm RFC-855
TELNET OPTION SPECIFICATIONS
.It Cm RFC-856
TELNET BINARY TRANSMISSION
.It Cm RFC-857
TELNET ECHO OPTION
.It Cm RFC-857
TELNET SUPPRESS GO AHEAD OPTION
.It Cm RFC-858
TELNET SUPPRESS GO AHEAD OPTION
.It Cm RFC-1073
TELNET WINDOW SIZE OPTION
.It Cm RFC-1091
TELNET TERMINAL-TYPE OPTION
.Sh BUGS
Since TELNET connections do not have a username assigned to it, there
will be no username present for TELNET gateway users in the conference.
.Pp
The terminal type submitted by the remote side is converted to lower case.
.Pp
.Nm Vchatd
never sends
.Tn TELNET
.Dv IAC GA
commands.
.Sh COPYRIGHT
Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001
.Pp
by Andreas S. Wetzel
.Pp
All rights reserved.