int VReadGraphs (FILE *file, VAttrList *attrs, VGraph **graphs) { return VReadObjects(file, VGraphRepn, attrs, (VPointer **)graphs); }
int VReadEdges (FILE *file, VAttrList *attributes, VEdges **edge_sets) { return VReadObjects (file, VEdgesRepn, attributes, (VPointer **) edge_sets); }
int VReadImages (FILE *file, VAttrList *attributes, VImage **images) { return VReadObjects (file, VImageRepn, attributes, (VPointer **) images); }