Man pages matching name fgetgrent_r in section 3:

fgetgrent_r.3.en	debian 10 / manpages-dev
fgetgrent_r.3.ja	debian 10 / manpages-ja-dev
fgetgrent_r.3.en	debian 11 / manpages-dev
fgetgrent_r.3.ja	debian 11 / manpages-ja-dev
fgetgrent_r.3.en	debian 12 / manpages-dev
fgetgrent_r.3.ja	debian 12 / manpages-ja-dev