From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hugo Mills <hugo@carfax.org.uk>
Subject: Re: your mail
Date: Tue, 20 Sep 2011 16:35:40 +0100
Message-ID: <20110920153540.GE21530@carfax.org.uk>
References: <c627c52800e0bb4e7884aa7174cb4a18@www.jots.org>
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Cc: linux-btrfs@vger.kernel.org
To: File's@jots.org, checksum?@jots.org
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On Tue, Sep 20, 2011 at 11:24:30AM -0400, Ken D'Ambrosio wrote:
> Just wondering if/how one goes about getting the btrfs checksum of a given
> file.  Is there a way?

   Checksums are computed on individual 4k blocks, not on the whole
file. There's no explicit interface for retrieving checksums, but if
you understand the data structures, you can get hold of the checksums
for a file using the BTRFS_IOC_TREE_SEARCH ioctl.

   Hugo.

-- 
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
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