#include <ifaddrs.h>
#include <stdio.h>

int main(int argc, char **argv)
{
        struct ifaddrs *inet;
        
        if (getifaddrs(&inet) < 0) {
                fprintf(stderr, "error in getifaddrs()");
                exit(-1);
        }

        struct ifaddrs *i;

        for (i = inet; i != NULL; i = i->ifa_next) {
                fprintf(stdout, "i=%x, i->next=%x\n", i, i->ifa_next);
                fprintf(stdout, "ifa_name = %s\n", i->ifa_name);
        }

        freeifaddrs(inet);
        return 0;
}


__OUTPUT__
ayaz$ gcc -o test test.c && ./test 
i=8049a88, i->next=8049b0c
ifa_name = lo
i=8049b0c, i->next=8049b90
ifa_name = eth0
i=8049b90, i->next=8049c14
ifa_name = lo
i=8049c14, i->next=0
ifa_name = eth0
[~] [laptop]