How to programmatically check if running on HHVM?

Question

I need to run a given package on both HHVM runtime and traditional PHP runtime. My question: is there a way to check programmatical

Answer 1

Some older versions of HHVM don't have HHVM_VERSION defined. They all output "HipHop" in phpinfo().

function is_hhvm(){
  ob_start();
  phpinfo();
  $info=ob_get_contents();
  ob_end_clean();
  return ($info=='HipHop');
}