pub unsafe extern "C" fn g_io_add_watch_full(
channel: *mut GIOChannel,
priority: i32,
condition: u32,
func: Option<unsafe extern "C" fn(_: *mut GIOChannel, _: u32, _: *mut c_void) -> i32>,
user_data: *mut c_void,
notify: Option<unsafe extern "C" fn(_: *mut c_void)>
) -> u32