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Date: Fri, 11 Sep 1998 09:30:18 -0600
From: Erik Ratcliffe <erik@caldera.com>
To: caldera-users@rim.caldera.com
Subject: Re: Editing your PATH (fwd

On Thu, Sep 10, 1998 at 09:11:28PM -0500, Alan Jackson wrote:
> I would *love* to see a document describing how Caldera boots up through
> to X and the window manager. I've never quite figured it all out.

Here's a quickie (anyone out there who has corrections, feel free to chime
in):


                              Power On
                                 |
                                 V
                             BIOS (CMOS)
                                 |
                                 V
                         Boot Loader (LILO)
                                 |
                 ________________V_________________
                 |         |          |            |
                DOS      OS/2      Whatever      Linux
                 .         .          .            |
                 .         .          .            V
                 V         V          V     Bootstrap Kernel
                                                   |
                                 ---               V
                                |        /sbin/init is executed
                                |                  |
                                |                  V
                                |        /etc/inittab is read **
                                |    (default runlevel is set here)
                                |                  |
                                |                  V
                                |   /etc/rc.d/rc#.d stuff is executed **
                                |   (default runlevel scripts are here)
                                |                  |
                   SysV Init. --|                  V
                                |    /etc/rc.d/rc.boot is executed
                                |                  |
                                |                  V
                                |   /etc/rc.d/rc.modules is executed
                                |                  |
                                |                  V
                                |    /etc/rc.d/rc.local is executed **
                                |                  |
                                |                  V
                                |        /bin/login is executed
                                 ---


          ** Odds are you will change the way your system boots
             by modifying the items listed in these locations


As for booting to X-Windows (which is what I think you are asking to do),
there is a default runlevel in /etc/inittab (indicated by the number in the
"initdefault" line) that tells what runlevel you will start in.  If this is
3, you'll start in regular multi-user mode (no X-based login).  If you
change this to 5, you will start in the same runlevel but with an X-based
login, provided by xdm (by default).  For runlevel 3, all the scripts in
/etc/rc.d/init.d that are symbolically linked to the /etc/rc.d/rc3.d
directory will be executed; for runlevel 5, all the /etc/rc.d/init.d scripts
that have symbolic links sitting in /etc/rc.d/rc5.d will be executed.  As
you may have guessed, the "#" in "rc#.d" is replaced with the runlevel
number. 

Xdm, by the way, uses etc/X11/wmconfig/xsessionrc for its settings (note
/that this is a hard link to xinitrc, which is used to start default X
services when you use plain ol' startx to start up X.  It is in the same
directory as xsessionrc; change one file, and you'll simultaneously change
the other).  The window manager is usually executed at the end of xsessionrc
(or, in the case of a plain ol' startx session, xinitrc).

I hope that helps...

-- 
| (o)(o)     Erik Ratcliffe, erik@caldera.com    |
|  \oo/   Caldera Systems, Inc.  Orem, Utah USA  |
|  =\/=           http://www.caldera.com         |