Tested on Debian kfreebsd-amd64. The BSD #includes worked. Both statfs64
and statfs worked. Using statfs to keep the same as general freebsd, and
because I didn't try it on 32 bit.
At least on OSX 10.6.6 it appears to have the same defintions as
FreeBSD. The build process doesn't complain and the code is enabled,
this needs to be tested and checked more.