On 04/21/2012 12:21 AM, Stefan Tomanek wrote: > How would you achieve the following with tar alone? > > find / -xdev -cnewer /var/backups/lastrun -path '/var/cache/*' ! -type d > -prune -o -print0 -fls /var/backups/filelist \ | > tar cpf - --no-unquote --no-recursion --null -T -
This looks like a simple incremental update of / so I'd use tar's incremental-dump features, and use the --exclude-caches* or --exclude-tag* options to selectively exclude components of /var/cache. > Then -T should probably removed from tar. No, -T is useful in a trusting environment. It's only backups, where the users aren't necessarily trusted, that are the problem. Getting back to the original suggestion. It strikes me that when dumping a live tree, the kind of diagnostic that one should get is a "file changed as we read it" diagnostic, since the problem occurs only when a directory is modified between the time that tar did a readdir and the time that tar did the corresponding open. And perhaps we would need a different diagnostic for this issue, and once we did that then you could address the issue with the --warning=KEYWORD option. Just thinking aloud -- I haven't actually read the code recently or anything.
