Hi, I was wondering what the purpose is of the macros APR_DECLARE_OPTIONAL_FN and APR_RETRIEVE_OPTIONAL_FN. For example, in mod_authn_dbd APR_RETRIEVE_OPTIONAL_FN is used to get a hold on the functions ap_dbd_acquire and ap_dbd_prepare declared in in mod_dbd with APR_DECLARE_OPTIONAL_FN. I could also directly invoke these functions as they are declared in the header file mod_dbd.h and let the loading of the module fail with an unresolved symbol if mod_dbd is not loaded. What is the benefit for using those macros?
Cheers, Andrej
