우분투에서의 전역 키보드 이벤트에 대해 질문을 올리고자 합니다.

#include <X11/Xlib.h>
#include <stdio.h>
int main()
{
    Window root;
    XEvent e;
 
    int iKeyCode;
    int iKeyState;
    int iKeyTime;
 
    // Open the display
    Display *dpy = XOpenDisplay(0);
    if (!dpy) return 1;
    // Get the root window -- so keys will be global
    root = DefaultRootWindow(dpy);
 
    // wait for events
    for(;;) {
        XGrabKeyboard(dpy, root, 1, GrabModeAsync, GrabModeAsync, CurrentTime);
        XNextEvent(dpy, &e);
        iKeyCode = e.xkey.keycode;
        iKeyState = e.xkey.state;
        iKeyTime = e.xkey.time;
        //int iKeyType = e.type;
        Window tmp = e.xkey.window;
        XUngrabKeyboard(dpy, CurrentTime);
 
        XPutBackEvent(dpy, &e);
        XSelectInput(dpy, tmp, KeyPressMask | KeyReleaseMask);
        XGrabKey(dpy, iKeyCode, None, tmp, 1, GrabModeAsync, GrabModeAsync);
        XNextEvent(dpy, &e);
 
        //XSendEvent(disp, InputFocus, FALSE, xev.type, &xev);
        XAllowEvents(dpy, ReplayKeyboard, iKeyTime);
        if (e.type == KeyPress){
            // 나중에 사운드 재생
            printf("Pressed!!\n");
        }
    }
 
    return 0;
}