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Just wondering if/how one goes about getting the btrfs checksum of a given file. Is there a way? Thanks! -Ken -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 == PGP key: 515C238D from wwwkeys.eu.pgp.net or http://www.carfax.org.uk --- "How deep will this sub go?" "Oh, she''ll go all the way to --- the bottom if we don''t stop her."
[Your Reply-to: header was screwed up, so I''m sending this again. From: Ken D''Ambrosio <ken@jots.org> Reply-to: File''s@jots.org, checksum?@jots.org ] On Tue, Sep 20, 2011 at 04:35:40PM +0100, Hugo Mills wrote:> 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 == PGP key: 515C238D from wwwkeys.eu.pgp.net or http://www.carfax.org.uk --- "How deep will this sub go?" "Oh, she''ll go all the way to --- the bottom if we don''t stop her."