Events: use eventfd() instead of syscall(SYS_eventfd) if possible.

This fixes --with-file-aio support on systems that lack eventfd()
syscall, notably aarch64 Linux.

The syscall(SYS_eventfd) may still be necessary on systems that
have eventfd() syscall in the kernel but lack it in glibc, e.g.
as seen in the current CentOS 5 release.
3 files changed
tree: 0d7c14c86d7186f9dc5779a04ae8a532d9295883
  1. auto/
  2. conf/
  3. contrib/
  4. docs/
  5. misc/
  6. src/
  7. .hgtags