How to Check kernel version in code?

[Benjamin Kaduk]

On Tue, 3 Jun 2014, Sreenivasa Honnur wrote:

> I want to enable some code based on FBSD kernel versions like below:
>
> #ifdef FreeBSD_VERSION_10
>
> #endif
>
> #ifdef FreeBSD_VERSION_9.2
>
> #endif
>
>
> How can I do achieve this?

__FreeBSD_version is defined in sys/param.h, and is incremented for major 
version changes as well as other events of note.

Increments are tabulated at 
http://www.freebsd.org/doc/en/books/porters-handbook/freebsd-versions.html

-Ben Kaduk