NS rr set from libdns

Hello;
I recently began using the libdns routines to make my C program to
DNS lookups. As advertised, it's fun! It's easy!

...at least for A, MX and TXT records. Elegant simplicity itself,
and a little C function I can easiy call, for each RR type.

But, what about NS records? There isn't a routine for that
that I can see, or see easily and a this point I'm under the
impression I have to hack one up. I can not believe this is right.

Am I missing something? Is there some best common practice to
use libdns to get an NS rr set that I don't know about?

What would you do to get NS records with libdns?

Please and thank you,
Richard