---
title: sf_detach_func
framework: Kernel
role: symbol
role_heading: Type Alias
platforms: [macOS 10.4+]
path: kernel/sf_detach_func
---

# sf_detach_func

## Declaration

```occ
typedef void (*sf_detach_func)(void *cookie, socket_t so);
```

## Parameters

- `cookie`: Cookie value specified when the filter attach was called.
- `so`: The socket the filter is attached to.

## Return Value

Return Value If you return a non-zero value, your filter will not be attached to this socket.

## Discussion

Discussion sf_detach_func is called to notify the filter it has been detached from a socket. If the filter allocated any memory for this attachment, it should be freed. This function will be called when the socket is disposed of.