The release notes have a minor rant about the kernel's tempfile api, starting out by calling it 'almost good'. :) The complaints boil down to: 1. how openat() indicates that the file system does not support that operation -> It returns either EISDIR or ENOENT, when ENOSYS or OPNOTSUPP or even EINVAL might be more precise choices. 2. linkat() doesn't support the AT_REPLACE flag even though there was a patch for it submitted nearly 10 years ago that was even approved by Linus. Anyway, here's hoping that one or both of these get fixed.