On Sat, Aug 12, 2017 at 07:44:14PM -0700, Dan Williams wrote:
How about MAP_SYNC == (MAP_SHARED|MAP_PRIVATE)? On older kernels
should get -EINVAL, and on new kernels it means SYNC+SHARED.
Cute trick, but I'd hate to waster it just for our little flag.
#define __MAP_VALIDATE MAP_SHARED|MAP_PRIVATE
#define MAP_SYNC 0x??? | __MAP_VALIDATE
so that we can reuse that trick for any new flag?