XSetInputFocus(3X11)

NAME
       XSetInputFocus, XGetInputFocus - control input focus

SYNTAX
       XSetInputFocus(display, focus, revert_to, time)
             Display *display;
             Window focus;
             int revert_to;
             Time time;

       XGetInputFocus(display, focus_return, revert_to_return)
             Display *display;
             Window *focus_return;
             int *revert_to_return;

ARGUMENTS
       display   Specifies the connection to the X server.

       focus     Specifies the window, PointerRoot, or None.

       focus_return
                 Returns the focus window, PointerRoot, or None.

       revert_to Specifies where the input focus reverts to if
                 the window becomes not viewable.  You can pass
                 RevertToParent, RevertToPointerRoot, or
                 RevertToNone.

       revert_to_return
                 Returns the current focus state (RevertToParent,
                 RevertToPointerRoot, or RevertToNone).

       time      Specifies the time.  You can pass either a
                 timestamp or CurrentTime.

DESCRIPTION
       The XSetInputFocus function changes the input focus and
       the last-focus-change time.  It has no effect if the spec-
       ified time is earlier than the current last-focus-change
       time or is later than the current X server time.  Other-
       wise, the last-focus-change time is set to the specified
       time (CurrentTime is replaced by the current X server
       time).  XSetInputFocus causes the X server to generate
       FocusIn and FocusOut events.

       Depending on the focus argument, the following occurs:

       +o    If focus is None, all keyboard events are discarded
            until a new focus window is set, and the revert_to
            argument is ignored.

       +o    If focus is a window, it becomes the keyboard's focus
            window.  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.

       +o    If focus is PointerRoot, the focus window is dynami-
            cally taken to be the root window of whatever screen
            the pointer is on at each keyboard event.  In this
            case, the revert_to argument is ignored.

       The specified focus window must be viewable at the time
       XSetInputFocus is called, or a BadMatch error results.  If
       the focus window later becomes not viewable, the X server
       evaluates the revert_to argument to determine the new
       focus window as follows:

       +o    If revert_to is RevertToParent, the focus reverts to
            the parent (or the closest viewable ancestor), and
            the new revert_to value is taken to be RevertToNone.

       +o    If revert_to is RevertToPointerRoot or RevertToNone,
            the focus reverts to PointerRoot or None, respec-
            tively.  When the focus reverts, the X server gener-
            ates FocusIn and FocusOut events, but the last-focus-
            change time is not affected.

       XSetInputFocus can generate BadMatch, BadValue, and Bad-
       Window errors.

       The XGetInputFocus function returns the focus window and
       the current focus state.

DIAGNOSTICS
       BadValue  Some numeric value falls outside the range of
                 values accepted by the request.  Unless a spe-
                 cific 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 generate this error.

       BadWindow A value for a Window argument does not name a
                 defined Window.

SEE ALSO
       XWarpPointer(3X11) 
       Xlib - C Language X Interface