How do I get my IP address in C on Linux? [duplicate]

Question

How could I get my IP address (preferably in 192.168.0.1 format)?

Answer 1

This example code lists both the interface name (e.g. lo or eth0) together with the currently assigned IP address, for all the IPv4 network interfaces that exist on your computer:

getifaddrs(&addrs);
tmp = addrs;

while (tmp) 
{
    if (tmp->ifa_addr && tmp->ifa_addr->sa_family == AF_INET)
    {
        struct sockaddr_in *pAddr = (struct sockaddr_in *)tmp->ifa_addr;
        printf("%s: %s\n", tmp->ifa_name, inet_ntoa(pAddr->sin_addr));
    }

    tmp = tmp->ifa_next;
}

freeifaddrs(addrs);

Answer 2

For Linux:

To get all interfaces local to the machine use getifaddrs().

There is an example at the end of the page linked above.