Xlib: Events vom Root-Window abfragen

[TrollSlayer]

Hallo!
Wie kann ich Events für root window (Desktop-Hintergrund) mit Xlib abfangen? XSelectInput mit root window als Argument liefert einen Fehler bei der Ausführung :mad: :

X Error of failed request: BadAccess (attempt to access private resource denied)
Major opcode of failed request: 2 (X_ChangeWindowAttributes)
Serial number of failed request: 9
Current serial number in output stream: 9

Der Code sieht so aus:
/* ... */
dis = XOpenDisplay(NULL);
myWin = (Window *) RootWindow(dis, 0);
XMapWindow(dis, (int) myWin);

XSelectInput(dis, (int) myWin, ExposureMask | KeyPressMask |
ButtonPressMask);
/* ... */

[pik7]

hallo,



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

int main()
{

XEvent ev;
Display *disp;
Window win;

disp = XOpenDisplay(NULL);
win = DefaultRootWindow(disp);

XSelectInput(disp, win, KeyPressMask | ExposureMask);

while(1)
{

XNextEvent(disp,&ev);

switch(ev.type)
{

case KeyPress: printf("Taste gedrückt\n");break;
case Expose: printf("Expose Event\n");break;

}

}
return 1;

}



Xlib Programming Manual:

"Only one Cleint can select button events on any one window at one time, due to
the grab that automatically takes place."

und das wird dein Windowmanager sein

gruß

[TrollSlayer]

Danke!