Hi, I've just used dd(1) to repeatedly read an SD card until it got all the way through without an I/O error. Quite a bit of the run time was reading what had already been successfully read because I was lazy, or had a better way to use my time.
It occurred to me that ddrescue(1) would do a better job, but I wouldn't want a copy created in an output file. I skimmed https://www.gnu.org/software/ddrescue/manual/ddrescue_manual.html but didn't see a way to do this, or a special meaning to an output file of /dev/null. A --scrub would be quite handy to read repeatedly until the media's controller succeeds and re-maps the block internally. -- Cheers, Ralph.
