Getting the version level of FreeBSD for a ZFS boot environment that is mounted but not booted

uname -v gives me the version level of the booted environment. How can I get the version level of an environment without booting that environment? In the example below, a boot environment (BE) is mounted at a temporary path by TrueOS Desktop. I can access relevant parts of the file system but I don't know where to seek the required information: $ date ; uname -v Fri 25 Nov 2016 21:15:19 GMT FreeBSD 12.0-CURRENT #14 1717ae3(drm-next-4.7): Fri Oct 28 13:49:49 UTC 2016 root@gauntlet:/usr/obj/usr/src/sys/GENERIC $ beadm list BE Active Mountpoint Space Created Nickname initial - - 5.4G 2016-08-22 11:24 initial 20161005193649_201610142022 - - 3.1G 2016-10-14 20:22 12.0-CURRENT-up-20161014_204827 20161028134949_201610291803 - - 753.6M 2016-10-29 18:03 12.0-CURRENT-up-20161029_180801 20161028134949_14_201611081710 NR / 45.4G 2016-11-08 17:10 12.0-CURRENT-up-20161108_171012 12.0-CURRENT-up-20161125_173806 - - 7.5G 2016-11-25 17:12 12.0-CURRENT-up-20161125_173806 12.0-CURRENT-up-20161125_201510 - /tmp/BE-12.0-CURRENT-up-20161125_201510.nsZfNFVo 7.4G 2016-11-25 19:49 12.0-CURRENT-up-20161125_201510 $ ls -hl /tmp/BE-12.0-CURRENT-up-20161125_201510.nsZfNFVo total 215 drwxr-xr-x 2 root wheel 48B 25 Nov 19:56 bin drwxr-xr-x 10 root wheel 60B 25 Nov 20:15 boot drwxr-xr-x 3 root wheel 3B 25 Nov 20:02 compat -r--r--r-- 1 root wheel 6.0K 17 Aug 16:12 COPYRIGHT dr-xr-xr-x 2 root wheel 3B 22 Aug 11:31 dev -rw------- 1 root wheel 4.0K 25 Nov 19:48 entropy drwxr-xr-x 30 root wheel 129B 25 Nov 20:15 etc lrwxr-xr-x 1 root wheel 9B 22 Aug 11:35 home -> /usr/home drwxr-xr-x 4 root wheel 59B 25 Nov 19:56 lib drwxr-xr-x 4 root wheel 6B 25 Nov 19:56 libexec drwxr-xr-x 2 root wheel 2B 21 Nov 03:14 media drwxr-xr-x 2 root wheel 2B 8 Oct 12:21 mnt drwxr-xr-x 2 root wheel 2B 22 Aug 12:05 net drwxr-xr-x 2 root wheel 2B 22 Aug 11:25 packages -rw-r--r-- 1 root wheel 21K 25 Nov 20:15 pkg-add.log dr-xr-xr-x 2 root wheel 2B 17 Aug 16:12 proc drwxr-xr-x 2 root wheel 146B 25 Nov 19:56 rescue drwxr-xr-x 10 root wheel 21B 13 Nov 20:13 root drwxr-xr-x 2 root wheel 146B 25 Nov 19:56 sbin lrwxr-xr-x 1 root wheel 11B 17 Aug 16:12 sys -> usr/src/sys drwxr-xr-x 6 root wheel 8B 25 Nov 20:20 tmp drwxr-xr-x 17 root wheel 17B 22 Aug 11:32 usr drwxr-xr-x 28 root wheel 30B 25 Nov 20:11 var $ ### Reference FreeBSD manual page for beadm(1)