On Fri, 14 Dec 2012, John R. Towler wrote:
The topic is uname(1) and uname (3), sysctl -a entries and their
intended semantics in the English words of the man pages.
Sorry, I could not find a concise statement of your problem or
question.
I think you might be asking "how can the build system for some
other software tell what version of NetBSD is running?" If you
really need to know that, then I'd suggest "uname -r", sysctl
kern.osrelease, or the .release field of the struct returned
from the uname(3) library function; they all contain the same
information.
On the other hand, if your real question is "how can the build
system for some other product tell whether or not some feature is
available?", then the answer depends on the feature that you want
to test.
--apb (Alan Barrett)