Function gio_2_0_sys::g_input_stream_read_async

pub unsafe extern "C" fn g_input_stream_read_async(
    stream: *mut GInputStream, 
    buffer: *mut u8, 
    count: gsize, 
    io_priority: gint, 
    cancellable: *mut GCancellable, 
    callback: Option<GAsyncReadyCallback>, 
    user_data: gpointer
)