Or the parent could be trying to mv a file from one filesystem to another. In that case, mv will have to revert to a copy-then-delete operation, and the user ma

Or the parent could be trying to mv a file from one filesystem to another. In that case, mv will have to revert to a copy-then-delete operation, and the user may not have the permissions necessary to set up the new file with all the same metadata as the original.