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



NAME
     XGrabKeyboard, XUngrabKeyboard - grab the keyboard

SYNTAX
     int XGrabKeyboard(display, grab_window, owner_events,
     pointer_mode, keyboard_mode, time)
           Display *display;
           Window grab_window;
           Bool owner_events;
           int pointer_mode, keyboard_mode;
           Time time;

     XUngrabKeyboard(display, time)
           Display *display;
           Time time;

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.

     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.

     time      Specifies the time.  You can pass either a times-
               tamp or CurrentTime.

DESCRIPTION
     The XGrabKeyboard function actively grabs control of the
     keyboard and generates FocusIn and FocusOut events.  Further
     key events are reported only to the grabbing client.  XGrab-
     Keyboard overrides any active keyboard grab by this client.
     If owner_events is False, all generated key events are
     reported with respect to grab_window. If owner_events is
     True and if a generated key event would normally be reported
     to this client, it is reported normally; otherwise, the
     event is reported with respect to the grab_window. Both
     KeyPress and KeyRelease events are always reported, indepen-
     dent of any event selection made by the client.

     If the keyboard_mode argument is GrabModeAsync, keyboard
     event processing continues as usual. If the keyboard is



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     currently frozen by this client, then processing of keyboard
     events is resumed.  If the keyboard_mode  argument is Grab-
     ModeSync, the state of the keyboard (as seen by client
     applications) appears to freeze, and the X server generates
     no further keyboard events until the grabbing client issues
     a releasing XAllowEvents call or until the keyboard grab is
     released.  Actual keyboard changes are not lost while the
     keyboard is frozen; they are simply queued in the server for
     later processing.

     If pointer_mode is GrabModeAsync, pointer event processing
     is unaffected by activation of the grab. If pointer_mode is
     GrabModeSync, the state of the pointer (as seen by client
     applications) appears to freeze, and the X server generates
     no further pointer events until the grabbing client issues a
     releasing XAllowEvents call or until the keyboard grab is
     released.  Actual pointer changes are not lost while the
     pointer is frozen; they are simply queued in the server for
     later processing.

     If the keyboard is actively grabbed by some other client,
     XGrabKeyboard fails and returns AlreadyGrabbed.  If
     grab_window is not viewable, it fails and returns GrabNot-
     Viewable.  If the keyboard is frozen by an active grab of
     another client, it fails and returns GrabFrozen.  If the
     specified time is earlier than the last-keyboard-grab time
     or later than the current X server time, it fails and
     returns GrabInvalidTime.  Otherwise, the last-keyboard-grab
     time is set to the specified time (CurrentTime is replaced
     by the current X server time).

     XGrabKeyboard can generate BadValue and BadWindow errors.

     The XUngrabKeyboard function releases the keyboard and any
     queued events if this client has it actively grabbed from
     either XGrabKeyboard or XGrabKey.  XUngrabKeyboard does not
     release the keyboard and any queued events if the specified
     time is earlier than the last-keyboard-grab time or is later
     than the current X server time.  It also generates FocusIn
     and FocusOut events.  The X server automatically performs an
     UngrabKeyboard request if the event window for an active
     keyboard grab becomes not viewable.

DIAGNOSTICS
     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



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



               defined Window.

SEE ALSO
     XAllowEvents(3X11), XGrabButton(3X11), XGrabKey(3X11),
     XGrabPointer(3X11)
     Xlib - C Language X Interface

















































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