Function igraph_betweenness 

pub unsafe extern "C" fn igraph_betweenness(
    graph: *const igraph_t,
    weights: *const igraph_vector_t,
    res: *mut igraph_vector_t,
    vids: igraph_vs_t,
    directed: igraph_bool_t,
    normalized: igraph_bool_t,
) -> igraph_error_t