I should mention that this mechanism you're trying to use does not exist in Xlib. It can be done via the RECORD extension. I do not recommend it; among other things, X11 does not give programs "veto control" of event delivery --- so you could in theory use RECORD to do this (with significantly increased load over using the proper mechanism since you are seeing all key events) but you cannot prevent the triggering key(s) from also being delivered to the focused window. This is the wrong mechanism entirely for such things, operates at the wrong level, and is expensive (and potentially a security issue; consider what "all key events" means; this also means that the RECORD extension is often disabled in the interest of security).
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