Function lmflow_graph_observe_ex 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn lmflow_graph_observe_ex(
    g: *mut LMFlowGraph,
    port: *const c_char,
    observe_timestamp_bounds: bool,
    cb: Option<unsafe extern "C" fn(*mut c_void, LMFlowPacket)>,
    user: *mut c_void,
) -> i32