Always like to read history of operating systems and it's evaluation. As expected *BSD still following the standards unlike the linux :D

> As you might expect, all of the modern versions of su across Linux and the free BSDs support starting a login shell (cf the normal Linux su (also), FreeBSD su(1), NetBSD su(1), and OpenBSD su(1)). On Linux and OpenBSD, login isn't setuid root and so can't be used from a regular shell environment to become a new user; your only option is su. On FreeBSD and NetBSD,