XGrabKey(3X11)      RISC/os Reference Manual       XGrabKey(3X11)



NAME
     XGrabKey, XUngrabKey - grab keyboard keys

SYNTAX
     XGrabKey(display, keycode, modifiers, grab_window,
     owner_events, pointer_mode,
                  keyboard_mode)
           Display *display;
           int keycode;
           unsigned int modifiers;
           Window grab_window;
           Bool owner_events;
           int pointer_mode, keyboard_mode;

     XUngrabKey(display, keycode, modifiers, grab_window)
           Display *display;
           int keycode;
           unsigned int modifiers;
           Window grab_window;

ARGUMENTS
     display   Specifies the connection to the X server.

     grab_window
               Specifies the grab window.

     keyboard_mode
               Specifies further processing of keyboard events.
               You can pass GrabModeSync or GrabModeAsync.

     keycode   Specifies the KeyCode or AnyKey.

     modifiers Specifies the set of keymasks or AnyModifier.  The
               mask is the bitwise inclusive OR of the valid key-
               mask bits.

     owner_events
               Specifies a Boolean value that indicates whether
               the keyboard events are to be reported as usual.

     pointer_mode
               Specifies further processing of pointer events.
               You can pass GrabModeSync or GrabModeAsync.

DESCRIPTION
     The XGrabKey function establishes a passive grab on the key-
     board.  In the future, the keyboard is actively grabbed (as
     for XGrabKeyboard), the last-keyboard-grab time is set to
     the time at which the key was pressed (as transmitted in the
     KeyPress event), and the KeyPress event is reported if all
     of the following conditions are true:




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XGrabKey(3X11)      RISC/os Reference Manual       XGrabKey(3X11)



     ⊕    The keyboard is not grabbed and the specified key
          (which can itself be a modifier key) is logically
          pressed when the specified modifier keys are logically
          down, and no other modifier keys are logically down.

     ⊕    Either the grab_window is an ancestor of (or is) the
          focus window, or the grab_window is a descendant of the
          focus window and contains the pointer.

     ⊕    A passive grab on the same key combination does not
          exist on any ancestor of grab_window.

     The interpretation of the remaining arguments is as for
     XGrabKeyboard.  The active grab is terminated automatically
     when the logical state of the keyboard has the specified key
     released (independent of the logical state of the modifier
     keys).

     Note that the logical state of a device (as seen by client
     applications) may lag the physical state if device event
     processing is frozen.

     A modifiers argument of AnyModifier is equivalent to issuing
     the request for all possible modifier combinations (includ-
     ing the combination of no modifiers). It is not required
     that all modifiers specified have currently assigned Key-
     Codes.  A keycode argument of AnyKey is equivalent to issu-
     ing the request for all possible KeyCodes.  Otherwise, the
     specified keycode must be in the range specified by
     min_keycode and max_keycode in the connection setup, or a
     BadValue error results.

     If some other client has issued a XGrabKey with the same key
     combination on the same window, a BadAccess error results.
     When using AnyModifier or AnyKey, the request fails com-
     pletely, and a BadAccess error results (no grabs are esta-
     blished) if there is a conflicting grab for any combination.

     XGrabKey can generate BadAccess, BadValue, and BadWindow
     errors.

     The XUngrabKey function releases the key combination on the
     specified window if it was grabbed by this client.  It has
     no effect on an active grab.  A modifiers of AnyModifier is
     equivalent to issuing the request for all possible modifier
     combinations (including the combination of no modifiers).  A
     keycode argument of AnyKey is equivalent to issuing the
     request for all possible key codes.

     XUngrabKey can generate BadValue and BadWindow error.





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XGrabKey(3X11)      RISC/os Reference Manual       XGrabKey(3X11)



DIAGNOSTICS
     BadAccess A client attempted to grab a key/button combina-
               tion already grabbed by another client.

     BadValue  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.

SEE ALSO
     XAllowAccess(3X11), XGrabButton(3X11), XGrabKeyboard(3X11),
     XGrabPointer(3X11)
     Xlib - C Language X Interface





































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