group(5) on OpenBSD
The text b40a9e0cc1c2, as OpenBSD 5.1, OpenBSD 5.0, OpenBSD 4.9, OpenBSD 4.8, OpenBSD 4.7, OpenBSD 4.6 shipped it.
format of the group permissions file
The text b40a9e0cc1c2, as OpenBSD 5.1, OpenBSD 5.0, OpenBSD 4.9, OpenBSD 4.8, OpenBSD 4.7, OpenBSD 4.6 shipped it.
format of the group permissions file