---
title: cmsghdr
framework: Kernel
role: symbol
platforms: [macOS 10.6+]
path: kernel/cmsghdr
---

# cmsghdr

## Declaration

```occ
struct cmsghdr {
    ...
};
```

## Topics

### Instance Properties

- [cmsg_len](kernel/cmsghdr/1499136-cmsg_len.md)
- [cmsg_level](kernel/cmsghdr/1499367-cmsg_level.md)
- [cmsg_type](kernel/cmsghdr/1499189-cmsg_type.md)