NAME
        UnpackStructureTags -- unpack a structure to values in taglist. (V39)
   SYNOPSIS
        num = UnpackStructureTags(pack,packTable,tagList);
        D0                        A0   A1        A2
        ULONG UnpackStructureTags(APTR,ULONG *,struct tagitem *);
   FUNCTION
        For each table entry, a findtagitem() will be done and if the
        matching tag is found in the taglist, the data in the structure
        will be placed into the memory pointed to by the tag's ti_Data.
        ti_Data *must* point to a LONGWORD.
   INPUTS
        pack - a pointer to the data area to be unpacked
        packTable - a pointer to the packing information table.
                    See <utility/pack.h> for definition and macros
        tagList - a pointer to the taglist to unpack into
   RESULTS
        num - the number of tag items unpacked
   SEE ALSO
        <utility/pack.h>, findtagitem(), packstructuretags()