Small program to investigate handling multibyte keys in ncurses; based on another Github Gist.

debug_keycodes.c

/* 
    Adapted, with light modifications, from 
    
    https://gist.github.com/lesovsky/f0f5d31ac48f2fc53e5f
    
    The original name of the program was, "ncurses-get-key-code.c".
    
    The problem was the following:
    
    BACKGROUND:
    Normally, ncurses will read an arrow key, function key, or some other
"unusual" key as three bytes (the first byte of which seems to usually
be 27, or Escape.) The following program can be adapted to
demonstrate this, by removing the invocation to 'keypad': it can
be shown, for example, that pressing the 'home' key emits the sequence
27, 79, 72.
    The aforementioned ncurses function 'keypad' will cause such
unusual keys to be read as a _single_ integer code, facilitating that
that the value can be captured and handled by a program (as is done
below.)

    PROBLEM:
    I enabled 'keypad', but only arrow keys were being synthesized into
single-integer codes; function keys, along with the HOME key, were still
being read by the program as their original three-byte sequence.

    SOLUTION:
    The following Stack Overflow post helped:
    
    https://stackoverflow.com/questions/55357479/how-to-process-key-home-and-key-end-reliably-under-ncurses
    
    It turns out that the value of my TERM variable in my AntiX installation
was 'xterm-color', which was confusing ncurses working under this same
xterm. Simply setting TERM=xterm (and making that change persistent by
including it in my .bashrc) solves the problem!
    Incidentally, the person who provided the Stack Overflow answer, 
Thomas Dickey, was involved in the development of both ncurses and xterm!
    See 'https://invisible-island.net/'.
*/    
    
#include <ncurses.h>

int main()
{
    initscr();
    keypad(stdscr, true);   // Turn off the function-keys' reading mode
    noecho();               // Turn off the display of entered characters - you need it for getch()
    scrollok(stdscr, true); // Added to provide the user more lines to work with

    printw("Press F2 to exit.\n");

    bool exit = false;
    while ( !exit )
    {
        int ch = getch();

        switch ( ch )
        {
        case ERR:
            printw("Please, press any key...\n"); // If there was no pressing, we remind the user to press the key
            break;
        case KEY_F(2): // Exit the program if F2 was pressed
            exit = true;
            break;
        default:  // If everything is fine, we display the code of the pressed key
            printw("vvvvvvv\n");
            printw("Code of pressed key is %d\n", ch);
            printw("^^^^^^^\n");
            break;
        }

        refresh(); // Displaying on the real screen...
    }

    printw("Thank you. Good bye!");
    getch();
    endwin(); 
    return 0;
}