XNextEvent 抛出 BadAccess 错误与 ButtonPressMask

这是我的代码，我用它来实现非阻塞全局热键行为：

#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/time.h>
typedef struct
{
    Display *display;
    Window window;
} X11Data;

void handle_focus(X11Data& x11data)
{
    int revert_to_return = 0;
    XGetInputFocus(x11data.display, &x11data.window, &revert_to_return);
    if (x11data.window != None)
    {
        long EventMask = FocusChangeMask; //working
        EventMask |= KeyPressMask; //working
        EventMask |= PointerMotionMask; //working
        //EventMask |= ButtonPressMask; //non-working, BadAccess ((
        XSelectInput(x11data.display, x11data.window, EventMask);
    }
}
void some_op(XEvent& ev)
{
    //event processing actions
    printf("type %dn", ev.type);
    fflush(stdout);
}
void handle_event(X11Data& x11data)
{
    XEvent ev;
    XNextEvent(x11data.display, &ev);
    switch (ev.type)
    {
        case FocusOut:
        {
            x11data.window = None;
            break;
        }
        case KeyPress:
        {
            some_op(ev);
            break;
        }
        case MotionNotify:
        {
            some_op(ev);
            break;
        }
        case ButtonPress:
        {
            some_op(ev);
            break;
        }
        default: break;
    }
}
int main()
{
    X11Data x11data;
    x11data.display = XOpenDisplay(NULL);
    x11data.window = None;
    while (true)
    {
        if (x11data.window == None)
            handle_focus(x11data);
        else
            handle_event(x11data);
    }
    return 0;
}

一切正常，除了存在ButtonPressMask标志的情况 - 在这种情况下程序停止。我假设，我可以听键盘，但不能听鼠标。那么谁知道问题的根源和/或如何解决呢？