This is an old post, but you may be interested in xdotool (and libxdo). It’s an open source tool that helps you automate a bunch of the madness that is dealing with X11. It’ll help you simulate key and mouse events in addition to doing window operations (resize, move, close, unmap/map), and some window manager actions (move windows to another desktop, etc), and searching for windows by property and title.

* For some definition of “needed”.

I can get the window handler if i set the focus i become a Parameter error

X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 42 (X_SetInputFocus)
Serial number of failed request: 156
Current serial number in output stream: 157

My Problem is after a localhost Webserver Update i will send a ctrl+f5 to firefox for reload it not works for me
dbus and firefox as option the same

A word of warning to those who try to modify it: multiple calls to XOpenDisplay() with the same parameter return different handles; sending the press event with one handle and the release event with another will not work.

For some reason this doesn’t seem to send the key event to the focused window (a urxvt terminal in my case), but I read at this website (http://www.handhelds.org/moin/moin.cgi/GeneratingSyntheticX11Events) that a key event generated in this way is tagged as fake and many programs ignore events with that tag. However, as the site suggests, the thing to do is use the XTest function instead. So, I made this small change:

XSendEvent(event.display, event.window, True, KeyPressMask, (XEvent *)&event);
was changed to
XTestFakeKeyEvent(event.display, event.keycode, True, CurrentTime);

To complie this I had to do g++ -o XFakeKey XFakeKey.cpp -L/usr/X11R6/lib -lX11 -lXtst

Now it works perfectly.

Again, thank you.

Thank you very much for this excellent code. I have been searching for this for hours!

Best regards,
Benjamin

This method needs that the window is not minimized, maybe some hacker can find a method that is valid even if the window is minimized.

> But what I need is to be able to do is set keyboard focus
Feel free to correct me, what I’m using now is:

/*
* Window_With_Name: routine to locate a window with a given name on a display.
* If no window with the given name is found, 0 is returned.
* If more than one window has the given name, the first
* one found will be returned. Only top and its subwindows
* are looked at. Normally, top should be the RootWindow.
*/
Window
Window_With_Name(Display *display, Window top, const char *name)
{
Window *children, dummy;
unsigned int nchildren;
unsigned int i;
Window w=0;
char *window_name;

if (XFetchName(display, top, &window_name) && !strcmp(window_name, name))
return(top);

if (!XQueryTree(display, top, &dummy, &dummy, &children, &nchildren))
return(0);

for (i=0; i<nchildren; i++) {
w = Window_With_Name(display, children[i], name);
if (w)
break;
}
if (children) XFree ((char *)children);
return(w);
}

int
main(int argc, char *argv[])
{
display = XOpenDisplay(0);
if (!display)
exit(EXIT_FAILURE);

Window window_root = DefaultRootWindow(display);
if (!window_root)
exit(EXIT_FAILURE);

Window window_found = Window_With_Name(display, window_root, “put here the name of the window”);

if (window_found)
{
XSetInputFocus(display, window_found, RevertToNone, CurrentTime);

// Send keys to window_found

KeyPress event, serial 23, synthetic NO, window 0×4c00001,
root 0×59, subw 0×0, time 153093161, (423,461), root:(424,491),
state 0×10, keycode 43 (keysym 0×68, h), same_screen YES,
XLookupString gives 1 bytes: (68) “h”
XmbLookupString gives 1 bytes: (68) “h”
XFilterEvent returns: False

KeyRelease event, serial 26, synthetic NO, window 0×4c00001,
root 0×59, subw 0×0, time 153093232, (423,461), root:(424,491),
state 0×10, keycode 43 (keysym 0×68, h), same_screen YES,
XLookupString gives 1 bytes: (68) “h”
XFilterEvent returns: False

KeyPress event, serial 26, synthetic NO, window 0×4c00001,
root 0×59, subw 0×0, time 153093374, (423,461), root:(424,491),
state 0×10, keycode 31 (keysym 0×69, i), same_screen YES,
XLookupString gives 1 bytes: (69) “i”
XmbLookupString gives 1 bytes: (69) “i”
XFilterEvent returns: False

KeyRelease event, serial 26, synthetic NO, window 0×4c00001,
root 0×59, subw 0×0, time 153093434, (423,461), root:(424,491),
state 0×10, keycode 31 (keysym 0×69, i), same_screen YES,
XLookupString gives 1 bytes: (69) “i”
XFilterEvent returns: False

So, keycode 43 is ‘h’ and 31 is ‘i’ – *on my keyboard*. It may or may not be different for you.. I’m not really sure.

In any case, this should help a lot. I’ve been having troubles with Super and CTRL getting stuck on this new laptop somehow, so maybe I can use this to force a key-release…

getfocus(), keypress(), keyrelease() will not work
while
getfocus(), keypress(), getfocus(), keyrelease() works perfectly.

Thanks a lot.