Re: lvm-version -- beginning of wrapper (was: Re: lvm - I'll maintain it. - ITP lvm24)

[arthur@korn.ch]

Hi

Russell Coker schrieb:
> On 2000-12-14 18:14, Arthur Korn wrote:

>> >------ lvm-version
> >#! /bin/sh
> >
> >set -e
> >
> ># figure out the version of LVM in the kernel.
> 
> This is bad.  Proc shouldn't be mounted if it isn't there.  If you run "ps" 
> or "top" as root when /proc isn't mounted they don't try to mount it!  The 
> principle of least surprise should be used here.

AFAIK vgchange is usually run before /proc is mounted, so there
is no way around this, since if running vgchange fails, thats
bad ...

I introduced a conditional unmounting below, this should make
thing better:

> ># mount proc in case it is not yet there
> >if [ ! -f /proc/uptime ]; then
> >        [ -d /proc || mkdir /proc
> >	   mount -t proc none /proc
	   mount -t proc none /proc && $mounted_proc = yes
> >fi
> >
> ># check for lvm support
> >if [ ! -f /proc/lvm ]; then
>     modprobe lvm-mod
>     if [ ! -f /proc/lvm ]; then
> >        echo 'No lvm support in kernel.'
> >        exit 1
>     fi
> >fi
> 
> 
> >
> ># extract version number.
> >head -1 /proc/lvm |tr ' ' "\n"|grep '[0-9]\.[0-9]'

[ $mounted_proc ] && umount /proc

BTW: /etc/init.d/checkroot.sh mounts proc temporarily too.

ciao, 2ri
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