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

static Display* dpy;
static int scr;
static Window root;

#define     POSY    500
#define     POSX    500
#define     WIDTH   500
#define     HEIGHT  500
#define     BORDER  15

int main() {
    Window win;
    XEvent ev;

    if ((dpy = XOpenDisplay(NULL)) == NULL)
        err(1, "Can't open display");

    // Get default screen and root window
    scr = DefaultScreen(dpy);
    root = RootWindow(dpy, scr);

    // Creating the window
    win = XCreateSimpleWindow(dpy, root, POSX, POSY, WIDTH, HEIGHT, BORDER, BlackPixel(dpy, scr), WhitePixel(dpy, scr));

    // Map the window to the display server
    XMapWindow(dpy, win);

    while(XNextEvent(dpy, &ev) == 0) {

    }

    // Unmap the window
    XUnmapWindow(dpy, win);

    // Free resources
    XDestroyWindow(dpy, win);

    // Close the connection with the display server
    XCloseDisplay(dpy);

    return 0;
}