Print keycode of Mouse and Keyboard presses

keypress.c

#include <stdio.h>
#include <stdlib.h>
#include <X11/Xlib.h>

int main(int argsc, char *argv[]) {
    // Display
    Display *dpy;
    // Screen Id
    int screen;
    // Window
    Window win;
    // events inside window
    XEvent event;

    // Open Display
    dpy = XOpenDisplay(NULL);

    // Check is server is not null
    if (dpy == NULL) {
        fprintf(stderr, "Cannot open display!\n");
        exit(1);
    }

    // Connect to screen from server
    screen = DefaultScreen(dpy);

    // Basic window qith 500 x 300 size and 100,100 position
    win = XCreateSimpleWindow(dpy, RootWindow(dpy, screen), 100, 100, 500, 300, 1, BlackPixel(dpy, screen), WhitePixel(dpy, screen));

    // Define what Input events to select
    XSelectInput(dpy, win, ExposureMask | KeyPressMask | ButtonReleaseMask | ButtonPressMask);

    // maps the window and all of its subwindows that have map requests
    XMapWindow(dpy, win);

    // infinitely read next event
    while (1) {
        XNextEvent(dpy, &event);
        printf("BUTTON: %d\n", event.xkey.keycode);
        printf("-----------\n");
    }

    return 0;
}