Manpages - ares_set_local_ip4.3

ares_set_local_ip4 - Set local IPv4 address outgoing requests.

  #include <ares.h>

  void ares_set_local_ip4(ares_channel channel, unsigned int local_ip)

The ares_set_local_ip4 function sets the IP address for outbound requests. The parameter local_ip is specified in host byte order. This allows users to specify outbound interfaces when used on multi-homed systems.

*ares_set_local_ip6*(3)

This function was added in c-ares 1.7.4

Ben Greear