```
struct sockaddr_in6 server_addr;
server_addr.sin6_scope_id = if_nametoindex(p_global->ini_params.remote_nw_type);

```

This is the code line that is generating the error. I am working on ipv6. Please tell if there's a library that's missing for this or something else.

What on earth is `if_nametoindex` is doing and what value is desired for `sin6_scope_id`?