code: func RlimitStack() (cur uint64, err error) {
  	var r unix.Rlimit
  	err = unix.Getrlimit(unix.RLIMIT_STACK, &r)
  	return uint64(r.Cur), err // Type conversion because Cur is one of uint64, int64 depending on unix flavor.
  }
docs: // RlimitStack reports the current stack size limit in bytes.