The IETF uses a specific format for the standards and other documents it
publishes as RFCs, and for the draft documents which are produced when
developing documents for publications.

xml2rfc is one of a number of tools available to facilitate the formatting
of drafts and RFCs according to the existing rules. It takes as input an
xml file that contains the text and meta-information about author names
etc., and transforms it into suitably formatted output.

The input xml file should follow the grammars in RFC7749 (for v2 documents)
or RFC7991 (for v3 documents). Note that the grammar for v3 is still being
refined, and changes will eventually be captured in the bis draft for 7991
(also see https://ietf-tools.github.io/xml2rfc/).

To use PDF output, "pkg_add weasyprint noto-fonts roboto-fonts".