pam_getenv(3) on FreeBSD
The text 1349ccef7d5f, as FreeBSD 9.1-RELEASE, FreeBSD 9.0-RELEASE, FreeBSD 8.4-RELEASE, FreeBSD 8.3-RELEASE, FreeBSD 8.2-RELEASE, FreeBSD 8.1-RELEASE, FreeBSD 8.0-RELEASE, FreeBSD 7.4-RELEASE, FreeBSD 7.3-RELEASE, FreeBSD 7.2-RELEASE, FreeBSD 7.1-RELEASE, FreeBSD 6.4-RELEASE shipped it.
retrieve the value of a PAM environment variable