Man pages matching name explain_getdomainname_or_die in section 3:

explain_getdomainname_or_die.3.en	debian 10 / libexplain-dev
explain_getdomainname_or_die.3.en	debian 11 / libexplain-dev
explain_getdomainname_or_die.3.en	debian 12 / libexplain-dev