Linux Network Programming

Get list of network interfaces:
int getifaddrs(struct ifaddrs **ifap);
void freeifaddrs(struct ifaddrs *ifa);

inet_ntoa() and inet_aton() with IPv6 support
int inet_pton(int af, const char *src, void *dst);
const char *inet_ntop(int af, const void *src, char *dst, socklen_t size);