override_redirect Xlib window attribute does nothing

Question

I want to create a non-resizable window for my little game engine. I found out that override_redirect attribute set to true is exactly what I need. So I wrote my sample program:

#include <X11/Xlib.h>
#include <unistd.h>

     Display *display;
     Window  window;
     Visual  *visual;
     XSetWindowAttributes attributes;
     int depth;
     int screen;
 
int main(){
     display = XOpenDisplay(NULL);
     screen = DefaultScreen(display);
     visual = DefaultVisual(display,screen);
     depth  = DefaultDepth(display,screen);
     attributes.background_pixel = XWhitePixel(display,screen);
     attributes.override_redirect = True;

     window = XCreateWindow( display,XRootWindow(display,screen),
                            200, 200, 350, 200, 5, depth,  InputOutput,
                            visual ,CWBackPixel, &attributes);
     XSelectInput(display,window,ExposureMask | KeyPressMask) ;
     XMapWindow(display, window);
     XFlush(display);
     sleep(10);

     return 0;
}

However, my window is resizable and there is a title bar on the top of it. How can I get rid of those and why doesn't this code work as intended?

Answer 1

How can I get rid of those and why doesn't this code work as intended?

You forgot to set the CWOverrideRedirect bit in the bitmask:

CWBackPixel means that the background_pixel element in the attributes structure is considered.

You must use CWBackPixel|CWOverrideRedirect if both the elements background_pixel and override_redirect shall be considered:

 attributes.background_pixel = XWhitePixel(display,screen);
 attributes.override_redirect = True;

 window = XCreateWindow( display,XRootWindow(display,screen),
                        200, 200, 350, 200, 5, depth,  InputOutput,
                        visual, CWBackPixel|CWOverrideRedirect, &attributes);