A List function that updates the XmNselectedItems resource
#include <Xm/List.h> void XmListUpdateSelectedList Widget widget
XmListUpdateSelectedList frees the contents of the current XmNselectedItems list. The routine traverses the XmNitems list and adds each currently selected item to the XmNselectedItems list. For each selected item, there is a corresponding entry in the updated XmNselectedItems list.
For a complete definition of List and its associated resources, see XmList (3).