Registers event handler.
PRL_RESULT PrlHandle_RegEventHandler( PRL_HANDLE hObj, PRL_EVENT_HANDLER_PTR handler, PRL_VOID_PTR userData );
PrlApiCore.h
PRL_RESULT. Possible values: PRL_ERR_UNINITIALIZED - SDK was not properly initialized. PRL_ERR_INVALID_ARG - specified arguments are invalid. PRL_ERR_OUT_OF_MEMORY - not enough memory. PRL_ERR_SUCCESS - function completed successfully.