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

[Robert Huff]

Polytropon writes:
>  > If you do 'mix-and-match' where different parts of your system 
>  > come from different versions of FreeBSD you will have to keep
>  >  track of this yourself.
>
>  Such differences can occur if you
>  	1st - make update
>  	2nd - build and install world and kernel
>  	3rd - make update again
>  	4th - build and install kernel only
>  
>  It can as well happen if you "make install" for a certain part of
>  the OS (from the /usr/src tree) only.

	I would consider these wearing a giant karmic "Kick Me!" sign.
I've done it, but only rarely, with parts that don't change much,
and with code bases that are _at most_ a few days apart.


				Robert Huff