---
title: sockaddr_ctl
framework: Kernel
role: symbol
platforms: [macOS 10.13+]
path: kernel/sockaddr_ctl
---

# sockaddr_ctl

## Declaration

```occ
struct sockaddr_ctl {
    ...
};
```

## Discussion

Discussion The controller address structure is used to establish contact between a user client and a kernel controller. The sc_id/sc_unit uniquely identify each controller. sc_id is a unique identifier assigned to the controller. The identifier can be assigned by the system at registration time or be a 32-bit creator code obtained from Apple Computer. sc_unit is a unit number for this sc_id, and is privately used by the kernel controller to identify several instances of the controller.

## Topics

### Fields

- [sc_len](kernel/sockaddr_ctl/1809243-sc_len.md)
- [sc_family](kernel/sockaddr_ctl/1809246-sc_family.md)
- [ss_sysaddr](kernel/sockaddr_ctl/1809252-ss_sysaddr.md)
- [sc_id](kernel/sockaddr_ctl/1809255-sc_id.md)
- [sc_unit](kernel/sockaddr_ctl/1809262-sc_unit.md)
- [sc_reserved](kernel/sockaddr_ctl/1809263-sc_reserved.md)