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Date:   Mon, 4 Nov 2019 12:35:19 +0100
From:   Odin Hultgren van der Horst <odin@digitalgarden.no>
To:     linux-btrfs@vger.kernel.org
Subject: Extent to files
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I did a ioctl(FICLONE) IOCTL-FICLONERANGE(2) at some point later I want to be
able to check if the new file still shares all its physical storage with just
knowing the name of the new file.

I found some people suggesting to compare the files extents.

But the implementation I looked at knew both files used in the comparison,
so I was wondering if there a way to get all files that references a extent
in user space?

In reality I want a count off clones/(identical files) to a given file
in user space.