---
title: nd_opt_pref64_len
framework: Kernel
role: symbol
role_heading: Instance Property
platforms: [macOS 12.0+]
path: kernel/nd_opt_pref64/3754135-nd_opt_pref64_len
---

# nd_opt_pref64_len

## Declaration

```occ
u_int8_t nd_opt_pref64_len;
```