Query: History connectors sources of a given transitionPurpose: Returns the connectors that are sources of basic transitions in the input liststm_r_cn_source_of_bt (stm_list in_list,
int *status);
Query: Termination or history connectors targets of a given transitionPurpose: Returns the connectors that are targets of basic transitions in the input liststm_r_cn_target_of_bt (stm_list in_list,
int *status);