I asked this question: Why does du report a size of 0 for some non-empty files on a HFS+ partition?
There is another question: Directory size calculation difference that also treats this kind of problem, with
ls reporting different sizes for a file.
However, the problem is completely different in my question, and I found the answer with good references.
I know the questions look the same in surface, but mine is really HFS+ specific, and has the right answer (I think).
I don't really have the time to advocate for this question, as I already have the answer, but I know the answer is a bit tricky to find. Should I leave as it is ?