box = GEOSWKTReader_read(reader, "POLYGON((-112.0859375 33.4349975585938,-112.0859375 33.4675445556641,-112.059799194336 33.4675445556641,-112.059799194336 33.4349975585938,-112.0859375 33.4349975585938))");

record = dataset->data;
head = &(dataset->data);
/* keep records that match the criteria, otherwise delete them */
while(record != NULL) {
        char intersects;

        intersects = GEOSIntersects(record->geometry, box);

        if(intersects == 1) { /* record overlaps with box */
                head = &(record->next);
                record = record->next;
        } else { /* no overlap */
                *head = record->next;
                clusterGIS_Free_record(record);
                record = *head;
        }
}