[sr-dev] Calling external APIs

Hi, We are customising the kamailio for our use and hence we need to expose some our services API to kamailio (Core + Modules) .. We have to get variables from Kamailio and also need to pass back some variable values as parameters ... 1- With basic research, it is found that APIs can be registered to be called using Timer built in Kamailio. ? .. (Is this the only way to call functions) ? .. 2- What about calling a function when a specific event occurs in Kamailio ? .. Any starting point or detailed help in this regards will be appreciated .. With many thanks. Regards, Nasir Bhutta