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Date: 27 Oct 2001 14:45:00 +0200
From: kaih@khms.westfalen.de (Kai Henningsen)
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Subject: Re: [Q] pivot_root and initrd
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ebrower@usa.net (Eric)  wrote on 17.10.01 in <3BCDCF1D.6030202@usa.net>:

> You are simply doing the following, I assume with success:

>    exec /sbin/init "$@"

> whereas I am doing something like the following:

>    exec chroot . sh -c 'umount $OLDROOT; exec -a init.new /sbin/init
>      $INITARGS' <dev/console >dev/console 2>&1

> I am mystified that the call to 'exec /sbin/init' works if you are using
> the standard (you mention "based on RedHat7.1" util-linux") /sbin/init
> proggie, and that a standard RH7.1 initscripts would not complain when
> the root filesystem is already mounted r/w.

It works because the PID is 1, of course.

/linuxrc (or however you call it) runs with PID=1, so when it exec's /sbin/ 
init, the PID is still 1.

OTOH, you have chroot run a shell as a child, which therefore does *not*  
have PID=1.

MfG Kai