Function sd_bus_call_method 

pub unsafe extern "C" fn sd_bus_call_method(
    bus: *mut sd_bus,
    destination: *const c_char,
    path: *const c_char,
    interface: *const c_char,
    member: *const c_char,
    ret_error: *mut sd_bus_error,
    reply: *mut *mut sd_bus_message,
    types: *const c_char,
    ...
) -> c_int