mkdirat(2) on macOS
The text 6e969bc3033a, as macOS 10.14.6, macOS 10.14.3, macOS 10.14.2, macOS 10.14.1, macOS 10.13.6, macOS 10.13.5, macOS 10.13.4, macOS 10.13.3, macOS 10.13.2, macOS 10.13.1, macOS 10.13, macOS 10.12.6, macOS 10.12.5, macOS 10.12.4, macOS 10.12.3, macOS 10.12.2, macOS 10.12.1, macOS 10.12 shipped it.
make a directory file