Man pages matching name pack_fopen_chunk in section 3alleg4:

pack_fopen_chunk.3alleg4.en	debian 10 / allegro4-doc
pack_fopen_chunk.3alleg4.en	debian 11 / allegro4-doc
pack_fopen_chunk.3alleg4.en	debian 12 / allegro4-doc
pack_fopen_chunk.3alleg4.en	debian 13 / allegro4-doc