XGrabKey(XS)      X Version 11 (Release 5) 6 January 1993       XGrabKey(XS)


 Name

    XGrabKey - 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.

    grabwindow    Specifies the grab window.

    keyboardmode  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 keymask bits.

    ownerevents   Specifies a Boolean value that indicates whether the key-
                   board events are to be reported as usual.

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

 Description

    The XGrabKey function establishes a passive grab on the keyboard.  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:

    +  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 grabwindow is an ancestor of (or is) the focus window, or
       the grabwindow 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 grabwindow.

    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 (including the combination of no
    modifiers).  It is not required that all modifiers specified have
    currently assigned KeyCodes.  A keycode argument of AnyKey is equivalent
    to issuing the request for all possible KeyCodes.  Otherwise, the speci-
    fied keycode must be in the range specified by minkeycode and
    maxkeycode 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 AnyModif-
    ier or AnyKey, the request fails completely, and a ``BadAccess'' error
    results (no grabs are established) 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.

 Diagnostics


    ``BadAccess''  A client attempted to grab a key/button combination
                   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 generate this error.

    ``BadWindow''  A value for a Window argument does not name a defined Win-
                   dow.

 See also

    XAllowAccess(XS), XGrabButton(XS), XGrabKeyboard(XS), XGrabPointer(XS)
    Xlib - C Language X Interface