LN_PREV
len = fill_link_key(LN_PREV(nextlinkp), dfh, name);
(void) memcpy(LN_PREV(nextlinkp), prevkey, prevsize);
char *ptr = LN_PREV(prevlinkp);
(void) memcpy(LN_PREV(prevlinkp), ptr, LN_PREV_LEN(prevlinkp));
prevkey = ((prevsize > 0) ? LN_PREV(dellinkp) : NULL);
debug_print_key(fp, "prev", "", LN_PREV(linkp), LN_PREV_LEN(linkp));
linksize = fill_link_key(LN_PREV(linkp), &lastlinkp->dfh,
(void) memcpy(linkkey, LN_PREV(lastlinkp), linksize);
(void) memcpy(LN_PREV(lastlinkp), linkkey, linksize);