Hello

you can use two great tools to do this:
1. Christoph Lange's structclass
2. CLSHeap.prg from Ed Rauh

you can find both in the download section ..
i think Christoph has even an example of a point structure in the documentation of the Structclass

otherwise check out Wiki's WednesdayNightLectures , there are two articles called Pointers on Pointers which describes how to use clsheap.prg
and api funcionts in general

regards

Christian