Issue with XQuartz

[alepi]

Hi all,
I have an issue with XQuartz and haven't found the "issues" page so I am starting a discussion. Feel free to remove it if inappropriate.

When closing the window in this program, it shuts down the connection with X server and exit with 1 instead of testing for a destroy event and exit gracefully with 0 as I expected. I tried another Xlib tutorial with different code and I get the same behaviour.

I admit that I am a beginner with X but I am surprised that this happens.

Thanks for helping out.

I am on macOS Mojave and XQuartz version is 2.8.1. Here is my source:

#include <stdint.h>

#include<stdio.h>
#include<stdlib.h>

#include<X11/Xlib.h>
#include<X11/Xutil.h>
#include<X11/Xatom.h>

int main(int argc, char** args)
{
    int width = 800;
    int height = 600;

    Display* display = XOpenDisplay(0);
    if(!display)
    {
        printf("No display available\n");
        exit(1);
    }

    uint64_t root = DefaultRootWindow(display);
    int defaultScreen = DefaultScreen(display);

    int screenBitDepth = 24;
    XVisualInfo visinfo = {};
    if(!XMatchVisualInfo(display, defaultScreen, screenBitDepth, TrueColor, &visinfo))
    {
        printf("No matching visual info\n");
        exit(1);
    }

    XSetWindowAttributes windowAttr;
    windowAttr.background_pixel = 0;
    windowAttr.colormap = XCreateColormap(display, root,
                 visinfo.visual, AllocNone);
    windowAttr.event_mask = StructureNotifyMask;
    unsigned long attributeMask = CWBackPixel | CWColormap | CWEventMask;

    Window window = XCreateWindow(display, root,
                                  0, 0,
                                  width, height, 0,
                                  visinfo.depth, InputOutput,
                                  visinfo.visual, attributeMask, &windowAttr);
    if(!window)
    {
        printf("Window wasn't created properly\n");
        exit(1);
    }
    
    XStoreName(display, window, "Hello, World!");

    XMapWindow(display, window);
    XFlush(display);

    int windowOpen = 1;
    while(windowOpen)
    {
        XEvent ev = {};
        while(XPending(display) > 0)
        {
            XNextEvent(display, &ev);
            switch(ev.type)
            {
                case DestroyNotify: {
                    XDestroyWindowEvent* e = (XDestroyWindowEvent*) &ev;
                    if(e->window == window)
                    {
                        XDestroyWindow(display, window);
                        windowOpen = 0;
                    }
                } break;
                default: {
                    printf("unknown event type: %d\n", ev.type);
                } break;
            }
        }
    }
    
    XCloseDisplay(display);

    return 0;
}

[alepi]

Turns out it was my lack of knowledge about X protocol. Please feel free to remove this discussion.