https://man.openbsd.org/OpenBSD-6.3/resolv.conf.5
https://mail-index.netbsd.org/port-arm32/1998/10/25/0006.html
https://man7.org/linux/man-pages/man5/resolv.conf.5.html
https://serverfault.com/questions/732325/how-to-persist-resolv-conf-options-such-as-rotate-timeout-in-centos
https://www.freebsd.org/cgi/man.cgi?resolv.conf
https://www.shellhacks.com/setup-dns-resolution-resolvconf-example/
https://github.com/NLnetLabs/ldns/blob/develop/dnssec_verify.c
// https://github.com/ogham/dog/blob/master/dns-transport/src/tls_stream.rs
// https://www.rfc-editor.org/rfc/rfc7858#ref-BCP195
// https://github.com/rustls/tokio-rustls