I mean on Linux you're not encumbered by this because the syscall api is stable but in practice most GNU/Linux distros assume glibc. You can't correctly resolve a hostname on Linux without farming out to glibc -- hell even the kernel punts to userspace for dns names but you can technically ignore it if you want.

On BSDs and macOS you're always SOL because the syscall api isn't stable and only the C wrappers are.