How do I determine the FreeBSD "world" revision/version?

[Ian Bonnycastle]

Good afternoon everyone,

I'm asking this question here because I honestly don't know where to turn to
otherwise. I've looked through forums, Google search results and the FreeBSD
handbook without a specific answer. I understand the concept that FreeBSD is
actually an OS, which is a combination of the kernel and the "world". Ports
are the extraneous userland which is not mandatory for a working system.
Now, in order to explain my question, I have to use an analogy: In Linux,
you can have a kernel version, a distribution version and software versions.
If you're running kernel 2.6.20, CentOS (as an example) 5.1, and bash
(another example) 3.2, you know that upgrading can occur at any of those
levels.

My actual question is this: Is there a way to tell what version of the
FreeBSD world you're running outside of "uname -a", which tells you what
*kernel* version you're running? I do know that any of these can be patched
to different levels outside of what you've installed from scratch (or
upgraded to at any particular level), but with Linux, when you run the
respective commands, you get the *base* revision you started from. In
FreeBSD, "uname -a" gives you the kernel "base", and "pkg_info" will give
you the software revision base for a particular port/package. If I have a
particular FreeBSD system, and know its a modified kernel, how can I tell
what base was originally on it? I've often updated the kernel on a
7.1-RELEASE to 7-STABLE to get more recent updates to the kernel, but the
base as been left at 7.1-RELEASE. Now, it could have been 7.0-RELEASE or
7.x-RELEASE and after upgrading the kernel, is this informaiton stored
anywhere?

Also, if this *is* explained somewhere, and I've missed, I honestly
apologize in advance.

Thanks,

Ian

-- 
So drop on the deck and flop like a fish.