Simple ncurses app not reacting to arrow keys - ncurses

Question

I compiled this simple ncurses program and the up down keys are unresponsive.
Any idea why this does not work?
I am using Fedora Linux 5.7.16-200.fc32.x86_64 the default terminal emulator is XTerm(351). I got no errors or warning building ncurses or making the app.
cc -o test test.c -lncurses
/* test.c */
#include <stdlib.h>
#include <stdio.h>
#include <curses.h>
int main(void) {
WINDOW * mainwin, * childwin;
int ch;
/* Set the dimensions and initial
position for our child window */
int width = 23, height = 7;
int rows = 25, cols = 80;
int x = (cols - width) / 2;
int y = (rows - height) / 2;
/* Initialize ncurses */
if ( (mainwin = initscr()) == NULL ) {
fprintf(stderr, "Error initialising ncurses.\n");
exit(EXIT_FAILURE);
}
/* Switch of echoing and enable keypad (for arrow keys) */
noecho();
keypad(mainwin, TRUE);
/* Make our child window, and add
a border and some text to it. */
childwin = subwin(mainwin, height, width, y, x);
box(childwin, 0, 0);
mvwaddstr(childwin, 1, 4, "Move the window");
mvwaddstr(childwin, 2, 2, "with the arrow keys");
mvwaddstr(childwin, 3, 6, "or HOME/END");
mvwaddstr(childwin, 5, 3, "Press 'q' to quit");
refresh();
/* Loop until user hits 'q' to quit */
while ( (ch = getch()) != 'q' ) {
switch ( ch ) {
case KEY_UP:
if ( y > 0 )
--y;
break;
case KEY_DOWN:
if ( y < (rows - height) )
++y;
break;
case KEY_LEFT:
if ( x > 0 )
--x;
break;
case KEY_RIGHT:
if ( x < (cols - width) )
++x;
break;
case KEY_HOME:
x = 0;
y = 0;
break;
case KEY_END:
x = (cols - width);
y = (rows - height);
break;
}
mvwin(childwin, y, x);
}
/* Clean up after ourselves */
delwin(childwin);
delwin(mainwin);
endwin();
refresh();
return EXIT_SUCCESS;
}

Answer 1

The example doesn't repaint the child-window (so nothing seems to happen), and doesn't use cbreak (so nothing happens until you press Return (i.e., newline).
I did this change to see what it does:
> diff -u foo.c.orig foo.c
--- foo.c.orig 2020-08-30 06:00:47.000000000 -0400
+++ foo.c 2020-08-30 06:02:50.583242935 -0400
## -29,6 +29,7 ##
/* Switch of echoing and enable keypad (for arrow keys) */
+ cbreak();
noecho();
keypad(mainwin, TRUE);
## -85,6 +86,7 ##
}
mvwin(childwin, y, x);
+ wrefresh(childwin);
}
Some terminal descriptions may use the same character ControlJ for cursor-down (and get mapped into KEY_ENTER rather than KEY_DOWN—see source code). After allowing for the other two problems, you may be seeing that.