This is taken from the website:
http://www.jonshouse.co.uk/xlogin.cgi

At the moment this code is Beta quality, its feature complete but doesen't work as intended from a security point of view, all connections run with access controls disabled.

xlogin is a login manager similar in function to xdm, gdm, kdm etc. It does not use any xdm code and has very few dependencies. It can run as both a stand alone command "xlogin" or with the optional XDMCP server "xlogin-xdmcpserver". Automatic logins are also possible. The package has man pages provided.

Features :

     * Everything is available on the command line, great for use with init
     * Supports simple shell scripts for starting each desktop environment
     * Use command line switches to enforce policy (desktops, wallpapers etc)
     * all settings stored in /etc/ - no hunting for settings or hastles with backups
     * automatic logins available with -autologin command line switch and xlogin-makeidentity utility
     * Persistant connection attempts to X servers, configure displays and turn it on/off at will
     * xdmcp server with MIT-COOKIE-1 authentication (Well sort off !)


Example 1 :
A machine with Xvnc installed - Want a simple login window to always be available for the server. Runlevel should be 3 and/or 5 for redhat based distributions (fedora etc) and 2 for Debian based distros (Debian ubuntu etc).
/etc/inittab

vnc1:35:respawn:/usr/bin/Xvnc -once -ac -rfbport 5901 -geometry 1024x768 -alwaysshared --securitytypes=none :5 
xlo1:35:respawn:/usr/bin/xlogin -display localhost:5 -date -background tree -default KDE


Example 2 :
Any number of X terminals can connect with -query, use this for Xvnc as well
/etc/inittab

vnc1:35:respawn:/usr/bin/Xvnc -once -ac -rfbport 5901 -geometry 1024x768 -alwaysshared --securitytypes=none -query localhost :5 
xdm1:35:respawn:/usr/bin/xlogin-xdmcpserver -date -background tree -default GNOME


Example 3 :
Xvnc server with a perminant KDE session for user "alwayson", Create the user with xlogin-makeidentity
/etc/inittab

vnc1:35:respawn:/usr/bin/Xvnc -once -ac -rfbport 5901 -geometry 1024x768 -alwaysshared --securitytypes=none :5 
xlo1:35:respawn:/usr/bin/xlogin -identity alwayson -date -background tree -desktop KDE


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