---
name: "ares_set_local_ip6"
section: "3"
platform: "linux"
package: "c-ares"
version: "1.34.9-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ares_set_local_ip6"
---

# ares\_set\_local\_ip6(3)

Set local IPv6 address outgoing requests.

## NAME

ares\_set\_local\_ip6 - Set local IPv6 address outgoing requests.

## SYNOPSIS

```
#include <ares.h>
void ares_set_local_ip6(ares_channel_t *channel, const unsigned char* local_ip6)
```

## DESCRIPTION

The **ares\_set\_local\_ip6** function sets the IPv6 address for outbound IPv6 requests.  The parameter *local\_ip6* is specified in network byte order. This allows users to specify outbound interfaces when used on multi-homed systems.  The *local\_ip6* argument must be 16 bytes in length.

## SEE ALSO

[**ares\_set\_local\_ip4**(3)](/ares_set_local_ip4/3.md)

## NOTES

This function was added in c-ares 1.7.4