Man pages matching name stpncpy in section 3:

stpncpy.3.en	debian 10 / manpages-dev
stpncpy.3.es	debian 10 / manpages-es
stpncpy.3.ja	debian 10 / manpages-ja-dev
stpncpy.3.pt	debian 10 / manpages-pt-dev
stpncpy.3.en	debian 11 / manpages-dev
stpncpy.3.es	debian 11 / manpages-es-dev
stpncpy.3.fr	debian 11 / manpages-fr-dev
stpncpy.3.ja	debian 11 / manpages-ja-dev
stpncpy.3.pt	debian 11 / manpages-pt-dev
stpncpy.3.en	debian 12 / manpages-dev
stpncpy.3.ja	debian 12 / manpages-ja-dev