The clonetagitems() function is used to copy an existing tag array into a
new tag array.

    struct TagItem *otags;      /* Original tag array */
    struct TagItem *ntags;      /* New tag array */

    /* Make sure there is a TagItem array */
    if (otags)
    {
        /* Copy the original tags into a new tag array */
        if (ntags = CloneTagItems(otags))
        {
            /* ...do something with the array... */

            /* Free the array when your done with it */
            FreeTagItems (ntags);
        }
    }

This function can also be used to implement a function that will insert
tag items into an array.

    struct TagItem *otags;      /* Original tag array */
    struct TagItem *tags;       /* New tag array */

    /* Insert a couple of tags into an existing tag array */
    if (tags = MakeNewTagList (GA_LeftEdge, 10,
                               GA_TopEdge, 20,
                               TAG_MORE, otags))
    {
        /* ...do something with the array... */

        /* Free the array when your done with it */
        FreeTagItems (tags);
    }

    /* This function will create a tag array from tag pairs placed on
     * the stack */
    struct TagItem *MakeNewTagList (ULONG data,...)
    {
        struct TagItem *tags = (struct TagItem *) &data;

        return (CloneTagItems (tags));
    }