Man pages matching name getgrent_r in section 3:

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