Function steamworks_sys::register_rust_steam_callback

pub unsafe extern "C" fn register_rust_steam_callback(
    parameter_size: c_int, 
    userdata: *mut c_void, 
    run_func: extern "C" fn(_: *mut c_void, _: *mut c_void), 
    dealloc: extern "C" fn(_: *mut c_void), 
    callback_id: c_int, 
    game_server: c_int
) -> *mut c_void