On Tue, 24 Oct 2006, Girish Venkatachalam wrote:
> Dear friends,
>
> I know this question sounds basic but it is not.
>
> How to programmatically determine the IP address of an interface?
>
> (Programmatically means using C of course :-)
>
> getsockname(2) is supposed to work but it doesn't since it returns 0.0.0.0
> for INADDR_ANY. getpeername(2) works, so am I supposed to send a packet, do a
> getpeername(2) at the other side and get back the result in the payload?
>
> Till now I have got away with a system("/sbin/ifconfig -a | grep.... hack.
>
> Am I missing something? I surely am since the very notion of IP address of an
> interface is silly since it could be bridged,carped, trunked etc.
>
> But say, I have obtained 192.168.1.2 thro' DHCP and this is what I want to
> figure out. That is the only IP that interface has. How to achieve that?
You are looking for getifaddrs(3)
-Otto
