Function cnd_timedwait 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn cnd_timedwait(
    cnd: *mut cnd_t,
    mtx: *mut mtx_t,
    timeout: *const timespec,
) -> c_int

See https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_timedwait.html.