Does this idiom (which turns out to be broken on rename op failure for most FSs) work reliably with ZFS (on the same filesystem)? def atomically_write(file

Does this idiom (which turns out to be broken on rename op failure for most FSs) work reliably with ZFS (on the same filesystem)? def atomically_write(filename, data): with open(filename + '.tmp', 'w') as fh: fh.write(data) os.rename(filename + '.tmp', filename) In addition to ordering guarantees, you also need to guarantee that even in case of failure the rename operation leaves the to-be-renamed file as it is and the to-be-renamed-to file non-existent – is that the case? > If only every filesystem was like that.. I wonder if the solution for databases and other server software that needs to persist data reliably is just pretend they are and insist on end-users sticking to non-broken filesystems (most probably ZFS, assuming the set is currently non-empty). The alternative of wasting endless time and resources on sysiphean quests to placate crap filesystems seems to have been an utter failure so far.