Man pages matching name localeconv in section 3:

localeconv.3.de	debian 10 / manpages-de-dev
localeconv.3.en	debian 10 / manpages-dev
localeconv.3.es	debian 10 / manpages-es
localeconv.3.ja	debian 10 / manpages-ja-dev
localeconv.3.pt	debian 10 / manpages-pt-dev
localeconv.3.de	debian 11 / manpages-de-dev
localeconv.3.en	debian 11 / manpages-dev
localeconv.3.es	debian 11 / manpages-es-dev
localeconv.3.fr	debian 11 / manpages-fr-dev
localeconv.3.ja	debian 11 / manpages-ja-dev
localeconv.3.pt	debian 11 / manpages-pt-dev
localeconv.3.de	debian 12 / manpages-de-dev
localeconv.3.en	debian 12 / manpages-dev
localeconv.3.es	debian 12 / manpages-es-dev
localeconv.3.fr	debian 12 / manpages-fr-dev
localeconv.3.ja	debian 12 / manpages-ja-dev
localeconv.3.ru	debian 12 / manpages-ru-dev