Linux ncurses getch

The `getch()` function is a blocking input function in the ncurses library of Linux. It waits for the user to press a key on the keyboard and returns the corresponding integer value of the key pressed.

Here is a simple example of using `getch()` to read a single character from the user:

#include <ncurses.h>

int main()
{
    initscr();  // initialize ncurses
    cbreak();   // don't wait for the Enter key to be pressed
    noecho();   // don't print the character on the screen
    keypad(stdscr, TRUE);   // enable function keys

    printw("Press any key to continue...");
    refresh();  // redraw the screen
    getch();    // wait for a keypress

    endwin();   // restore terminal settings
    return 0;
}

In this example, `initscr()` initializes ncurses, `cbreak()` puts the terminal into cbreak mode (which means input is immediately available to the program without waiting for the Enter key to be pressed), `noecho()` disables the automatic printing of input characters to the screen, and `keypad()` enables function keys.

The `printw()` function prints a message to the screen, and `refresh()` redraws the screen. Finally, `getch()` waits for a keypress, and `endwin()` restores the terminal settings before exiting the program.

Note: The return value of `getch()` is an integer, but most keys on the keyboard have an ASCII code that corresponds to their value. For example, the ASCII code for the 'A' key is 65. You can use `getch()` to read the ASCII code of a key by casting the result to a `char`. For example:

char ch = (char)getch();