SilcBool silc_idcache_update(SilcIDCache cache, SilcIDCacheEntry entry,
                                 void *new_id, char *new_name,
                                 SilcBool free_old_name);

    Updates cache `entry' with new values.  If the `new_id' is non-NULL
    then the new value will be copied over the old value in the `entry'
    unless the ID doesn't exist, when the `new_id' will be stored in `entry'.
    If the `new_name' is non-NULL then the `entry' will be updated with
    `new_name'.  The caller is responsible of freeing the old name if it
    was updated with new one.  The old ID value does not need to be freed
    as the new value is copied over the old value.  If the `free_old_name'
    is TRUE the library will free the old name from the entry.