handle the case when eventfd is present at compilation time but not supported by the system
handle the case when eventfd is present at compilation time but not supported by the system

Ignore-this: 60d0bbeebf1433be7fe5781f95d0f289

darcs-hash:20110407161259-c41ad-2af6352f016602b627af5c2a93e2f6a8fa8c40c1.gz

avsm/lwt-OLD,avsm/lwt-OLD