How to get struct ISC_CLIENT_INTERFACE definition about Siebel Adaptive Communication API

 Dear Siebel Guru,

During process of develeoping customizing CTI driver, I can't find out definition of ISC_CLIENT_INTERFACE within API:

 ISCAPI ISC_RESULT RequestService
/* in */(ISC_DRIVER_HANDLE handle,
/* in */ const struct ISC_CLIENT_INTERFACE clntInterface,
/* in */ const ISC_STRING connectString,
/* in */ const struct ISC_KVParamList* datasetParams,
/* out */ ISC_SERVICE_HANDLE* serviceHandle);

I think if there are no struct ISC_CLIENT_INTERFACE definition, I couldn't obtain ISC_CLIENT_HANDLE to send event to siebel system. 

Anyone give me some help will be appreciated. thanks a lot!!!