Understanding XDM

[Polytropon]

On Sun, 24 Jun 2012 22:19:54 +0200, Christian Graulund wrote:
> Hello Guys,
> 
> I just install FreeBSD 9, and after compiling Xorg, I started trying to
> figure out how to install a Window Manager.
> When Following the handbook, I suggest installing XDM. I want to use
> something like Openbox, as my window manager, and I can't figure out if
> Openbox is a replacement for XDM, or something on top of XDM.

Not quite. XDM is the X display manager, a "GUI replacement"
for the login mechanism. It initiates the X session for the
user and loads his startup file, which calls the desired
window manager.



> I now there
> are alternative to XDM directly like LightDM ect., but the same questions
> applies to them.

Yes, there are other X display managers like KDM, GDM or WDM.
They are designed to work with a specific environment (KDE, Gnome,
WindowMaker in this example), but they can be used independently.



> So what is the function of XDM (or alternatives), and is it necessary to
> have to run a WM, or DE for that sake?

No, it's not neccessary. You can still perform the login the
traditional way (text mode console) and then call "startx" to
initiate your X session with the window manager or desktop
environment you want.

See "man xdm" for details. Also see your ~/.xinitrc and ~/.xsession
files for controlling what to do _after_ successful login, in
your example to "exec openbox" as the last step.

Sidenote: I've been using both XDM and WDM with WindowMaker
and XFCE (not Xfce -- XFCE means version 3, Xfce means version 4).
Works great. I prefer XDM, most secure and easy to use.




-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...