from man page
> uname -asnrvmpio
Darwin zchee-darwin-amd64.local 15.2.0 Darwin Kernel Version 15.2.0: Fri Nov 13 19:43:59 PST 2015; root:xnu-3248.20.55~1/RELEASE_X86_64 x86_64 i386 MacBookPro11,3 Darwin
> sw_vers
ProductName: Mac OS X
ProductVersion: 10.11.2
BuildVersion: 15C47a