XSetInputFocus(3X)                             XSetInputFocus(3X)



NAME
     XSetInputFocus, XGetInputFocus - control input focus

SYNOPSIS
     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;

DESCRIPTION
     The XSetInputFocus function changes the input focus and the
     last-focus-change time.  The function has no effect if the
     specified time is earlier than the current last-focus-change
     time or is later than the current X server time.  Otherwise,
     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 value of the focus argument, the following
     occurs:

          If focus is None, all keyboard events are discarded un-
          til a new focus window is set, and the revert-to argu-
          ment is ignored.

          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 re-
          ported relative to the focus window.

          If focus is PointerRoot, the focus window is dynamical-
          ly 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 unviewable, the X server
     evaluates the revert-to argument to determine the new focus
     window as follows:

          If revert-to is RevertToParent, the focus reverts to
          the parent (or the closest viewable ancestor), and the



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XSetInputFocus(3X)                             XSetInputFocus(3X)



          new revert-to value is taken to be RevertToNone.

          If revert-to is RevertToPointerRoot or
          RevertToNone, the focus reverts to PointerRoot or None,
          respectively.  When the focus reverts, the X server
          generates FocusIn and FocusOut events, but the last-
          focus-change time is not affected.

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

   Arguments
     These functions accept the following arguments:

     display Specifies the connection to the X server.

     focus   Specifies the window ID, or either PointerRoot, or
             None.

     focus-return
             Returns the focus window ID, or either PointerRoot
             or None.

     revert-to
             Specifies the window to which the input focus re-
             verts if the window becomes unviewable.  You can
             pass one of the following constants:  RevertTo-
             Parent,
             RevertToPointerRoot, or RevertToNone.

     revert-to-return
             Returns the current focus state.  The function can
             return one of the following constants:  RevertTo-
             Parent, RevertToPointerRoot, or RevertToNone.

     time    Specifies the time.  You can pass either a times-
             tamp, expressed in milliseconds, or CurrentTime.

ERRORS
     BadMatch
             An argument or pair of arguments has the correct
             type and range but fails to match in some other re-
             quired way.

     BadValue
             A numeric value falls outside the range of values
             accepted by the request.  Unless a range is speci-
             fied 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



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XSetInputFocus(3X)                             XSetInputFocus(3X)



             A value for a Window argument does not name a de-
             fined window.

     The XSetInputFocus function can generate BadMatch,
     BadValue, and BadWindow errors.

SEE ALSO
     XWarpPointer(3X)

     Xlib - C Language Interface














































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