t ctx)
{
    int left_margin = ctx->text.left_margin;
    Bool visible = IsPositionVisible(ctx, ctx->text.insertPos);

    _XawTextShowPosition(ctx);

    if (visible && left_margin == ctx->text.left_margin) {
	int insert_line = LineForPosition(ctx, ctx->text.insertPos);
	int scroll_by = insert_line - (ctx->text.lt.lines >> 1);
	Boolean clear_to_eol = ctx->text.clear_to_eol;

	XawTextScroll(ctx, scroll_by, 0);
	SinkClearToBG(ctx->text.sink, 0, 0, XtWidth(ctx), XtHeight(ctx));
	ClearWindow(ctx);
	clear_to_eol = ctx->text.clear_to_eol;
	ctx->text.clear_to_eol = False;
	FlushUpdate(ctx);
	ctx->text.clear_to_eol = clear_to_eol;
    }
}

/*
 * Internal redisplay entire window
 * Legal to call only if widget is realized
 */
static void
DisplayTextWindow(Widget w)
{
    TextWidget ctx = (TextWidget)w;

    _XawTextBuildLineTable(ctx, ctx->text.lt.top, False);
    ClearWindow(ctx);
}

static void
TextSinkResize(Widget w)
{
    if (w && XtClass(w)->core_class.resize)
	XtClass(w)->core_class.resize(w);
}

/* ARGSUSED */
void
_XawTextCheckResize(TextWidget ctx)
{
    return;
}

/*
 * Converts (params, num_params) to a list of atoms & caches the
 * list in the TextWidget instance.
 */
Atom *
_XawTextSelectionList(TextWidget ctx, String *list, Cardinal nelems)
{
    Atom *sel = ctx->text.s.selections;
    Display *dpy = XtDisplay((Widget)ctx);
    int n;

    if (nelems > (Cardinal)ctx->text.s.array_size) {
	sel = (Atom *)XtRealloc((char *)sel, sizeof(Atom) * nelems);
	ctx->text.s.array_size = nelems;
	ctx->text.s.selections = sel;
    }
    for (n = nelems; --n >= 0; sel++, list++)
	*sel = XInternAtom(dpy, *list, False);
    ctx->text.s.atom_count = nelems;

    return (ctx->text.s.selections);
}

/*
 * Function:
 *	SetSelection
 *
 * Parameters:
 *	ctx	   - text widget
 *	defaultSel - default selection
 *	l	   - left and right ends of the selection
 *	r	   - ""
 *	list	   - the selection list (as strings).
 *	nelems	   - ""
 *
 * Description:
 *	Sets the current selection.
 *
 * Note:
 *	if (ctx->text.s.left >= ctx->text.s.right) then the selection is unset
 */
void
_XawTextSetSelection(TextWidget ctx, XawTextPosition l, XawTextPosition r,
		     String *list, Cardinal nelems)
{
    if (nelems == 1 && !strcmp (list[0], "none"))
	return;
    if (nelems == 0) {
	String defaultSel = "PRIMARY";
	list = &defaultSel;
	nelems = 1;
    }
    _SetSelection(ctx, l, r, _XawTextSelectionList(ctx, list, nelems), nelems);
}

/*
 * Function:
 *	ModifySelection
 *
 * Parameters:
 *	ctx   - text widget
 *	left  - left and right ends of the selection
 *	right - ""
 *
 * Description:
 *	Modifies the current selection.
 *
 * Note:
 *	if (ctx->text.s.left >= ctx->text.s.right) then the selection is unset
 */
static void
ModifySelection(TextWidget ctx, XawTextPosition left, XawTextPosition right)
{
    if (left == right)
	ctx->text.insertPos = left;
    _SetSelection(ctx, left, right, NULL, 0);
}

/*
 * This routine is used to perform various selection functions. The goal is
 * to be able to specify all the more popular forms of draw-through and
 * multi-click selection user interfaces from the outside.
 */
void
_XawTextAlterSelection(TextWidget ctx, XawTextSelectionMode mode,
		       XawTextSelectionAction action, String *params,
		       Cardinal *num_params)
{
    XawTextPosition position;
    Boolean flag;

    /*
     * This flag is used by TextPop.c:DoReplace() to determine if the selection
     * is okay to use, or if it has been modified.
     */
    if (ctx->text.search != NULL)
	ctx->text.search->selection_changed = True;

    position = PositionForXY(ctx, (int) ctx->text.ev_x, (int) ctx->text.ev_y);

    flag = (action != XawactionStart);
    if (mode == XawsmTextSelect)
	DoSelection(ctx, position, ctx-