From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Fri, 1 Sep 2000 13:47:08 +0200
From: Jan Niehusmann <jan@gondor.com>
Subject: [linux-lvm] Re: lvm.h kernel/userspace differences
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To: Andreas Dilger <adilger@turbolinux.com>
Cc: linux-lvm@msede.com

> - kernel's lv_v2_t has an additional field "uint8_t __unused;" _in the middle_
>   of the struct. Huh. What's that?

Additional information:

It's been included in linux-2.3.99-pre9 or -pre10. The patch was proposed by
Andrea Arcangeli in a mail to linux-kernel on Apr 5. He writes:

> o       inserts a pad in the lv_t structure to avoid breaking the
>         binary tools interface. I think everybody prefers to lose
>         32 bit per logical volume in the system than having to
>         change binary tools while switching between 2.2.x and 2.3.x
>         to make snapshotting to work :).