Man pages matching name callback in section 3:

callback.3.en	debian 10 / libffcall-dev
Callback.3.en	debian 10 / libvolpack1-dev
callback.3.en	debian 11 / libffcall-dev
Callback.3.en	debian 11 / libvolpack1-dev
callback.3.en	debian 12 / libffcall-dev
Callback.3.en	debian 12 / libvolpack1-dev