Re: [rdiff-backup-users] File change detection using hashes

[dean gaudet]

On Mon, 13 Feb 2006, Wiebe Cazemier wrote:

> Something _has_ to be devised to detect changes in files properly, to
> avoid files not being backed up. Perhaps you could try to implement an
> option for ctime checking, and possibly discover again why that's not
> possible. If it _is_ impossible, my --checksum-diffs should be
> implemented, IMO.

what you really want is something akin to rsync -c ... which forces 
checksumming of every file, regardless of mtime/size.

throwing more stat elements into the comparison is only approximately an 
improvement (you could also throw in dev:inode -- which would handle your 
mv situation most of the time, but breaks in some cases like snapshotting 
which preserves inode without preserving dev).


> And, would it be possible to check for changes occured in files _during_
> a backup with ctimes? That would be more reliable then mtimes.

ctime doesn't change when you modify the file, only mtime does.

-dean