Given a physical disk and an image created from it, I want to write the image back onto the physical disk, but only write the changed bytes or sectors. The use case is restoring images on an SSD - unlike HDDs these have a limited number of writes. The added reads do not cause wear on the SSD and might even speed up the restore process when barely anything changed.
writing this img [___|___|___|___|___|___|___|___|___] back onto this disk: [___|___|_ab|c__|___|___|___|xyz|___] actual writes: nnn nnn YYY YYY nnn nnn nnn YYY nnn
If the writes are not per-sector (here: 3-byte sectors) but bytewise that would work as well. A final statistic regarding the number of total writes would be nice, too.
dd can't do that, is there an existing tool for that?