openpam_set_feature(3) on FreeBSD
The text bc4dd2d77550, as FreeBSD 11.2-RELEASE, FreeBSD 11.1-RELEASE, FreeBSD 11.0-RELEASE, FreeBSD 10.4-RELEASE, FreeBSD 10.3-RELEASE, FreeBSD 10.2-RELEASE, FreeBSD 10.1-RELEASE shipped it.
enable or disable an optional feature