Man pages matching name allocate_voice in section 3alleg4:

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