I just learned about .rev
files with WinRAR -- where if you have a 10-part RAR volume, for example, plus one .rev
(recovery) volume -- the .rev
volume will be able to "fix" any one corrupted .rar
volume.
How is this possible? I don't understand how one volume could have all the data to fix any/all of the individually broken volumes.
I'd guess that it's perhaps possible in lieu of the volumes not being broken up "linearly", like I'm imagining, where each RAR volume holds distinct, individual files of the whole packed within; but rather, perhaps .rev
repairing is possible when the RAR volumes are viewed as one continuous file of bits and bytes, so to speak, and that perhaps there's some CRC'ish sorcery (ah hem, "repair work") involved to fix corrupted bytes.
But I just don't understand how you can have 9 working volumes with 1 damaged, yet have a recovery volume that can repair any one of the volumes. How is one volume able to hold data of "all" the volumes?