To have an overview what the listing database are, and how they fit into the entire database please read this document carefully.
In this papers only the used structures are explained in full details.
Listing data items are organized into listdata sets; each listdata set has its own database of keys, units, components and descriptors. Listdata sets are represented with on structure.
There is a container data structure, which is a union that can hold the data of any listdata type; referencing to the parent listdata set.
The structures below correspond to a specific entry; each of them represent one listdata type.