Function g_unix_fd_add_full
pub unsafe extern "C" fn g_unix_fd_add_full(
priority: i32,
fd: i32,
condition: u32,
function: Option<unsafe extern "C" fn(i32, u32, *mut c_void) -> i32>,
user_data: *mut c_void,
notify: Option<unsafe extern "C" fn(*mut c_void)>,
) -> u32