//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname favoriteAddrFamily
func favoriteAddrFamily(network string, laddr, raddr sockaddr, mode string) (family int, ipv6only bool) {
	switch network[len(network)-1] {
	case '4':
		return syscall.AF_INET, false
	case '6':
		return syscall.AF_INET6, true
	}