[Shapelib] Identify polygon by XY coordinate?

[shapelib-admin at lists.maptools.org]

List,
     I need a function that uses (X,Y) coordinates to identify the 
surrounding polygon in a shapefile, and then retrieve the associated 
attribute information for that polygon.
     Does anyone have a function like that?

Sincerely,
Bob Caldwell,
   Res. Assoc. Prof., Natural Resource Systems Analyst
   School of Natural Resources, University of Nebraska - Lincoln
   306 Keim Hall, P.O. Box 830910, Lincoln, NE 68583-0910
RCALDWELL1 at UNL.EDU    Phone: (402) 472-4792. FAX: (402) 472-7904.

http://cropmodelingworkshop.unl.edu/