ARES\_SET\_LOCAL\_DEV(3) Library Functions Manual ARES\_SET\_LOCAL\_DEV(3) # [NAME](#NAME) ares\_set\_local\_dev - Bind to a specific network device when creating sockets. # [SYNOPSIS](#SYNOPSIS) ``` #include void ares_set_local_dev(ares_channel_t *channel, const char* local_dev_name) ``` # [DESCRIPTION](#DESCRIPTION) The **ares\_set\_local\_dev** function causes all future sockets to be bound to this device with SO\_BINDTODEVICE. This forces communications to go over a certain interface, which can be useful on multi-homed machines. This option is only supported on Linux, the interface must not be already bound to the socket or the current effective user must have CAP\_NET\_RAW capability in the current network namespace for the option to work. If SO\_BINDTODEVICE is not supported or the setsockopt call fails (probably because of permissions), the error is silently ignored. # [SEE ALSO](#SEE_ALSO) [**ares\_set\_local\_ip4**(3)](/man/os/c-ares/ares_set_local_ip4.3) [**ares\_set\_local\_ip6**(3)](/man/os/c-ares/ares_set_local_ip6.3) [**network\_namespaces**(7)](/man/os/c-ares/network_namespaces.7) # [NOTES](#NOTES) This function was added in c-ares 1.7.4 23 September 2024 --- Document: ares_set_local_dev(3) from c-ares 1.34.8-r2 (Chainguard OS) Source: https://github.com/c-ares/c-ares