From mboxrd@z Thu Jan  1 00:00:00 1970
From: josv@osp.nl
Date: Wed, 22 Aug 2001 16:49:36 +0200
Subject: Re: [linux-lvm] how to determine if /dev/... is an LV?
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In-Reply-To: <20010822034425.F8742@pc.ilinx>; from 6888736b923846176364586bf2e7649f@interlinx.bc.ca on Wed, Aug 22, 2001 at 03:44:25AM -0400
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To: linux-lvm@sistina.com

Well,

You could always check the major number of the device file with
the one in /proc/devices, and see whether it is the major number
of the lvm driver. Then check whether the minor number is that
of a valid logical volume (not 0).

++Jos

And thus it came to pass that Brian J. Murrell wrote:
(on Wed, Aug 22, 2001 at 03:44:25AM -0400 to be exact)

> Hi all,
> 
> This should hopefully be simple.  I am modifying some code to deal
> with LVM.  If I am given a device path for an LV, say, /dev/VG/1,
> programatically, how can I determine that it actually is an LV and not
> some other kind of device?  The best I have come up with is:
> 
> lvdisplay -D -c /dev/VG/lvol1 2>&1 | grep "^/dev/VG/lvol1" >/dev/null
> 
> and testing "$?".
> 
> Seems kind of "hacky" though.  Is there a better way?
> 
> Also, is there any relationship between the output from the lvdisplay
> and the minor number for the device?
> 
> Thanx,
> b.
> 
> -- 
> Brian J. Murrell
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html

-- 
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