rem: return NULL;
add: hep = *hepp; if (hep == NULL) return NULL;  return (void *) hep->val;
context: hash_get(new_hash_table *nh, const void *key, ssize_t klen){	hash_entry *he;	he = *find_entry(nh, key, klen, NULL);	if (he)		return (void*)he->val;	return NULL;}