> Writing the same data back out should always be possible... Depends on the implementation: maybe you open a temp file and then mv it into place after you are

> Writing the same data back out should always be possible... Depends on the implementation: maybe you open a temp file and then mv it into place after you are done writing (for increased atomicity)? But as I already said, in practice we ignore these externalities because it makes the problem a lot harder for minor improvements — not because this isn't something software can "handle/resolve".