I thought so too, but found this reference to a Version 1 mkdir:
https://man.cat-v.org/unix-1st/1/mkdir
I recall reading a Version 6 or 7 man page about mkfs that included the
ability to populate a file system with some directories, and I thought that
implied that users couldn't create directories. The man page referenced
above hints that mkdir is run as the 'system user', presumably root, and
becomes the owner of new directories.
Rik
On Tue, Apr 29, 2025 at 4:28 AM Jaap Akkerhuis <jaapna(a)xs4all.nl> wrote:
I seem to remember that V7 was the first suystem which
had a mkdir system
call. That might have changed what ls -a showed.
jaap