getitimer(2) on FreeBSD
The text ea66f8ea7847, as FreeBSD 3.4-RELEASE, FreeBSD 3.3-RELEASE, FreeBSD 3.2-RELEASE, FreeBSD 3.1-RELEASE, FreeBSD 3.0-RELEASE, FreeBSD 2.2.9-RELEASE, FreeBSD 2.2.8-RELEASE, FreeBSD 2.2.7-RELEASE, FreeBSD 2.2.6-RELEASE shipped it.
get/set value of interval timer