Man pages matching name getprotobynumber in section 3:

getprotobynumber.3.en	debian 10 / manpages-dev
getprotobynumber.3.es	debian 10 / manpages-es
getprotobynumber.3.ja	debian 10 / manpages-ja-dev
getprotobynumber.3.pl	debian 10 / manpages-pl-dev
getprotobynumber.3.en	debian 11 / manpages-dev
getprotobynumber.3.fr	debian 11 / manpages-fr-dev
getprotobynumber.3.ja	debian 11 / manpages-ja-dev
getprotobynumber.3.pl	debian 11 / manpages-pl-dev
getprotobynumber.3.en	debian 12 / manpages-dev
getprotobynumber.3.es	debian 12 / manpages-es-dev
getprotobynumber.3.ja	debian 12 / manpages-ja-dev
getprotobynumber.3.pl	debian 12 / manpages-pl-dev