#include <Xm/Xm.h>#include <Xm/List.h>void do_list_click(Widget widget, caddr_t data1, XtPointer data2) {   char *string;   XmListCallbackStruct *callback = (XmListCallbackStruct *)data2;   XmStringGetLtoR(callback->item, XmSTRING_OS_CHARSET, &string);   printf("  You chose item %d : %s\n", callback->item_position, string);   XtFree(string);}int main(int argc, char **argv) {   Widget top_level, list;   XmString motif_strings[3];   Arg arg[4];   top_level = XtInitialize(argv[0], "test", NULL, 0, &argc, argv);   motif_strings[0] = XmStringCreateSimple("list item at index 0");   motif_strings[1] = XmStringCreateSimple("list item at index 1");   motif_strings[2] = XmStringCreateSimple("list item at index 2");   XtSetArg(arg[0], XmNitemCount, 3);   XtSetArg(arg[1], XmNitems, motif_strings);   XtSetArg(arg[2], XmNvisibleItemCount, 3); // all list elements are visible   XtSetArg(arg[3], XmNselectionPolicy, XmSINGLE_SELECT);   list = XmCreateList(top_level, "list", arg, 4);   XtAddCallback(list, XmNsingleSelectionCallback,		 (XtCallbackProc)do_list_click, NULL);   XtManageChild(list);   XtRealizeWidget(top_level);   XtMainLoop();   return 0;}