I would like to add support into exiv2 for some missing FujiFilm tags. Specifically, those listed in:

https://exiftool.org/TagNames/FujiFilm.html#IFD

which exiftool refers to as the IFD tags. While I am reasonably happy adding support for new tags, it appears that exiv2 does not currently understand block they are contained in. I would therefore appreciate some pointers as to what blocks inside tags_int I would need to modify.