XSetInputFocus causes the X server to generate FocusIn and FocusOut events. If a generated keyboard event would normally be reported to this window or one of its inferiors, the event is reported as usual. Otherwise, the event is reported relative to the focus window. The specified focus window must be viewable at the time XSetInputFocus is called, or a BadMatch error results. The XGetInputFocus function returns the focus window and the current focus state.
Some numeric value falls outside the range of values accepted by the request.
Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can gen- erate this error. BadWindow A value for a Window argument does not name a defined Window.