We don't need to explicitely use ncurses' scroll(). ncurses performs
vertical-motion optimization at wrefresh() time.

Using strace I confirmed that with the following patch curses still sends only
the new line of text to the terminal when scrolling up/down one line at a
time.

Signed-off-by: Benjamin Poirier <bpoir...@suse.de>
---
 scripts/kconfig/lxdialog/textbox.c |   55 +++++++----------------------------
 1 files changed, 11 insertions(+), 44 deletions(-)

diff --git a/scripts/kconfig/lxdialog/textbox.c 
b/scripts/kconfig/lxdialog/textbox.c
index 506a095..3b3c5c4 100644
--- a/scripts/kconfig/lxdialog/textbox.c
+++ b/scripts/kconfig/lxdialog/textbox.c
@@ -166,40 +166,12 @@ do_resize:
                case 'K':       /* Previous line */
                case 'k':
                case KEY_UP:
-                       if (!begin_reached) {
-                               int passed_end = 0;
-
-                               back_lines(page_length + 1);
-
-                               /* We don't call print_page() here but use
-                                * scrolling to ensure faster screen update.
-                                * However, 'end_reached' and 'page_length'
-                                * should still be updated, and 'page' should
-                                * point to start of next page. This is done
-                                * by calling get_line() in the following
-                                * 'for' loop. */
-                               scrollok(box, TRUE);
-                               wscrl(box, -1); /* Scroll box region down one 
line */
-                               scrollok(box, FALSE);
-                               page_length = 0;
-                               for (i = 0; i < boxh; i++) {
-                                       if (!i) {
-                                               /* print first line of page */
-                                               print_line(box, 0, boxw);
-                                               wnoutrefresh(box);
-                                       } else
-                                               /* Called to update 
'end_reached' and 'page' */
-                                               get_line();
-                                       if (!passed_end)
-                                               page_length++;
-                                       if (end_reached && !passed_end)
-                                               passed_end = 1;
-                               }
+                       if (begin_reached)
+                               break;
 
-                               print_position(dialog);
-                               wmove(dialog, cur_y, cur_x);    /* Restore 
cursor position */
-                               wrefresh(dialog);
-                       }
+                       back_lines(page_length + 1);
+                       refresh_text_box(dialog, box, boxh, boxw, cur_y,
+                                        cur_x);
                        break;
                case 'B':       /* Previous page */
                case 'b':
@@ -214,17 +186,12 @@ do_resize:
                case 'J':       /* Next line */
                case 'j':
                case KEY_DOWN:
-                       if (!end_reached) {
-                               begin_reached = 0;
-                               scrollok(box, TRUE);
-                               scroll(box);    /* Scroll box region up one 
line */
-                               scrollok(box, FALSE);
-                               print_line(box, boxh - 1, boxw);
-                               wnoutrefresh(box);
-                               print_position(dialog);
-                               wmove(dialog, cur_y, cur_x);    /* Restore 
cursor position */
-                               wrefresh(dialog);
-                       }
+                       if (end_reached)
+                               break;
+
+                       back_lines(page_length - 1);
+                       refresh_text_box(dialog, box, boxh, boxw, cur_y,
+                                        cur_x);
                        break;
                case KEY_NPAGE: /* Next page */
                case ' ':
-- 
1.7.7

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