Re: some dar format questions

Hey.

Thanks for your answers :-)

On Wed, 2019-01-16 at 13:47 +0100, Denis Corbin wrote:
> > 4) Am I right that "--delta no-patch" disables any use of binary 
> > deltas?
> 
> Not exactly. Binary delta is disabled by default. If an archive
> contains delta signatures (it has been built with --delta sig option)
> dar/libdar will by default use them during a differential backup and
> store a delta patch in place of the new version of the file's data.
> The delta patched is computed based on the delta signature found in
> the archive and the new version of the data found on filesystem.
> 
> the option "--delta no-patch" only instruct dar to ignore delta
> signature when present in an archive (or isolated catalogue) and to
> never perform a delta patch (always storing the whole data when data
> changed)

Well I think that's basically what I've meant above with "disables any
use of bin deltas".

When a fresh archive is created (i.e. not an incremental/differential
one), either with or without --delta no-patch, no binary deltas will be
used.

When creating an archive based on an incremental/differential one,...
with --delta no-patch any binary deltas present in the base archive,
will be "ignored" in the sense that the new archive will not store a
binary delta but the whole file (if there were changes).
While without --delta no-patch, it would, for files that already have a
binary delta in the base archive, create again binary deltas (if
necessary).

Right?


Cheers,
Chris.