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

# sf_getpeername_func

## Declaration

```occ
typedef int (*sf_getpeername_func)(void *cookie, socket_t so, struct sockaddr **sa);
```

## Parameters

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

## Return Value

Return Value If you return a non-zero value, processing will stop. If you return EJUSTRETURN, no further filters will be called but a result of zero will be returned to the caller of getpeername.

## Discussion

Discussion sf_getpeername_func is called to allow a filter to to intercept the getpeername function. When called, sa will point to a pointer to a socket address that was malloced in zone M_SONAME. If you want to replace this address, either modify the currenty copy or allocate a new one and free the old one.