#! /bin/sh
#
#	NAME
#		README -- readme file for xdm directory
#
#	SYNOPSIS
#		README
#
#	DESCRIPTION
#		Identifies the Tektronix customized xdm configuration
#		files and describes how it all works.
#
#	FILES
#		See below.
#
#	RCS VERSION
#		$Header: /tmp_mnt/vol/nwd/tools/media/X11/XP/bin/xdmconfig/RCS/README,v 1.4 1991/04/17 14:32:39 glennw Exp $
#

more << !EOF
		TEKTRONIX XDM CONFIGURATION FILES

INTRODUCTION

    Xdm manages a collection of X displays, both local and remote.  This
    directory, \\$TEKXP_ROOT/xdm, contains a collection of files which
    describe a sample configuration of xdm.  If your X terminal supports
    xdmcp (TekXpress does), you can get xdm and your X terminal running by
    as little as invoking xdm as root, e.g.

    xdm -config /usr/lib/X11/XP/xdm/xdm-config

    Only a few of the many configuration parameters which xdm can be tuned
    with are set in this sample.  Read the xdm manual page, xdm(1) for a
    complete description.

ENVIRONMENT VARIABLES
    DISPLAY
        points to the TekXpress display.  Overridden by the
        -display argument to XPstartup. 
    TEKXP_ROOT	
        contains the path to the XP directory tree that
        contains the following files.  Default is
        "/usr/lib/X11/XP". 
    XP_ROOT
        Old equivalent of TEKXP_ROOT used in V3 XPstartup;
        "/usr/lib/X11".  Overridden by TEKXP_ROOT. 

FILES
    The following files have been provided by Tektronix to support xdm
    for the Tektronix X Terminals:

    \$TEKXP_ROOT/xdm/xdm-config
	Xdm configuration file that defines xdm parameters.
	May by modified for the site administrator.

    \$TEKXP_ROOT/xdm/Xresources
	X resource definitions for the xdm authentication window.

    \$TEKXP_ROOT/xdm/Xsession
	The xdm Xsession script to be executed.

    \$TEKXP_ROOT/bin/XPstartup
	User environment initialization script, run from xdm Xsession.

    The following files may be used by XPstartup.  Read the XPstartup 
    script for details.

    \$TEKXP_ROOT/xdm/sample.Xresources
	A sample for the "site" or "user" \$HOME/.Xresources file that is 
	loaded on the server by XPstartup.

    \$TEKXP_ROOT/config/zzTek/Xsession
	Default X session script to be executed if a "user" or "site"
	session script is not found by XPstartup.

    \$TEKXP_ROOT/xdm/sample.Xsession
	A sample for the "site" or "user" X session file that is executed 
	by XPstartup.

INITIAL SETUP
    To use xdm with this files your system administrator will need to:

	1. If your X terminal does not support XDMCP (TekXpress does)
            add your X Terminal's display name to the "Xservers" file. 
	    For TekXpress terminals, you don't need to do this step.
	    The Xservers file is a list of those displays the xdm must
	    manage.  The configuration file \$TEKXP_ROOT/xdm/xdm-config
	    specifies the pathname for the Xservers file as
	    \$TEKXP_ROOT/xdm/Xdm-fileServers/Xservers

	    Syntax for each entry [refer to xdm(1)]:
		"<display_name> <display_type> <type-dependent_entry>"
	    For Example
		xenaray01:0	foreign		An XP27 in the Lab Area

	    valid display types are:
		local -- local display which receives multiple
		    sessions.
		localTransient -- local display which has only
		    one session run.
		foreign --  remote display which receives
		    multiple sessions.
		transient -- remote display which has only one
		    session run.

	    The type-dependent entry for local servers is a program name and
		its arguments.
	    The type-dependent entry for foreign servers (typically X
		Terminals) is ignored, but must contain at least one word.

	2. Execute xdm as root, using the file xdm-config or xdm-config.rel
	   as the configuration file:
	   	xdm -config <path of xdm config file>
    	   For example:
	   	# /bin/xdm -config \$TEKXP_ROOT/xdm/xdm-config
	   Or, if you have moved the TEKXP_ROOT tree somewhere else, 
	   	# cd $TEKXP_ROOT/xdm
	   	# $TEKXP_ROOT/bin/xdm -config xdm-config.rel
	   The latter case uses a feature of the xdm supplied in the TEKXP 
	   tree that allows xdm-config file entries to be current-directory 
	   relative.
	   Typically an entry should be added to a system boot process file,
	   e.g. /etc/rc.local, so that xdm is run when the host boots up, e.g.
		cd /usr/lib/X11/XPnew/xdm
		../bin/xdm -config xdm-config.rel
		cd /

OVERVIEW OF THE X SESSION
    If you decide to use the provided xdm configuration files (in
    particular \$TEKXP_ROOT/xdm/Xsession) then the user's session is
    defined by the script \$TEKXP_ROOT/bin/XPstartup.  See that script 
    for details about customizing your X session.

BUGS/CAVEATS
    If there is no traffic on a TCP connection, then there is no way for
    the host side to recognize that the X Terminal has been turned on and
    then turned off.  Doing periodic XSyncs and retrying to open the
    connection will take care of this, but you end up trading wasted cycles
    for activation time when the terminal is turned on.  This inability of
    xdm to notice when an X Terminal has powered off and on has prompted
    efforts by the X Consortium to extend the X Protocol with a set known
    as the "X Display Manager Control Protocol" or simply "XDMCP".
    Until then, if you use xdm your system administrator may need to
    restart the parent xdm process or kill the child xdm process associated
    with the X Terminal.  WARNING: killing the parent xdm process will kill
    all xdm subprocess and, thus, all session currently in progress.
!EOF
