Thanks for the ping. So I dug in a little further. The existing description is actually aligned with a library, mktemp.3 which has the same description. It can make not only directories, but pipes and fifos and... (etc) which are all normalized to files. Further, mktemp was written by Todd C Miller and even has a website https://www.mktemp.org/ and seems to have the same Nd in every single OS because we're all using the same implementation. So, we should not change it. In fact perhaps it should be in contrib/ to make that more obvious but I do not want to grind that axe.