BUF_LOCKFREE(9) on FreeBSD
The text 3c7f9d91e222, as FreeBSD 5.5-RELEASE, FreeBSD 5.4-RELEASE, FreeBSD 5.3-RELEASE, FreeBSD 5.2.1-RELEASE, FreeBSD 5.2-RELEASE, FreeBSD 5.1-RELEASE, FreeBSD 5.0-RELEASE shipped it.
destroys a buffer's lock
The text 3c7f9d91e222, as FreeBSD 5.5-RELEASE, FreeBSD 5.4-RELEASE, FreeBSD 5.3-RELEASE, FreeBSD 5.2.1-RELEASE, FreeBSD 5.2-RELEASE, FreeBSD 5.1-RELEASE, FreeBSD 5.0-RELEASE shipped it.
destroys a buffer's lock