See below for some sample X11 code that tracks events in *all* windows. Note that it uses the "create" event to select for input on newly-created windows.

#include <stdio.h> #include <stdlib.h> #include <X11/X.h> #include <X11/Xlib.h>

static void select(Display* dpy, Window w, long mask) { Window* children = NULL; unsigned count = 0; Window root, parent;

printf("Checking window %lx\n", w);

if (!XSelectInput(dpy, w, mask)) { fprintf(stderr, "Can't select input\n"); exit(1); } if (!XQueryTree(dpy, w, &root, &parent, &children, &count)) { fprintf(stderr, "Can't query tree\n"); exit(1); }

while (count-- > 0) { select(dpy, children[count], mask); }

if (children) { XFree(children); } }

int main(int argc, char* argv[]) {

Display* dpy = XOpenDisplay(NULL); Window root = XDefaultRootWindow(dpy); XEvent event; int quit = 0; long mask = KeyPressMask|KeyReleaseMask |PointerMotionMask|ButtonMotionMask |StructureNotifyMask|SubstructureNotifyMask;

const char* TYPE[LASTEvent] = { "0", "1", "KeyPress", "KeyRelease", "ButtonPress", "ButtonRelease", "MotionNotify", "EnterNotify", "LeaveNotify", "FocusIn", "FocusOut", "KeymapNotify", "Expose", "GraphicsExpose", "NoExpose", "VisibilityNotify", "CreateNotify", "DestroyNotify", "UnmapNotify", "MapNotify", "MapRequest", "ReparentNotify", "ConfigureNotify", "ConfigureRequest", "GravityNotify", "ResizeRequest", "CirculateNotify", "CirculateRequest", "PropertyNotify", "SelectionClear", "SelectionRequest", "SelectionNotify", "ColormapNotify", "ClientMessage", "MappingNotify", };

select(dpy, root, mask);

while (!quit) {

XNextEvent(dpy, &event); printf("Event: %s\n", TYPE[event.type]); switch (event.type) { case CreateNotify: select(dpy, event.xany.window, mask); break; case KeyRelease: quit = event.xkey.keycode == 24; break; default: break; } } exit(0); return 0; }