How can a rename not be atomic over a crash? What does a partially renamed state even mean? Surely, if I do "write foo~", "rename foo~ foo", regardless of any

How can a rename not be atomic over a crash? What does a partially renamed state even mean? Surely, if I do "write foo~", "rename foo~ foo", regardless of any crash, foo is either pointing to the old data or the new data. There simply isn't any inode with any "partially renamed state" mixing the two.