Table of Contents
XGrabKey, XUngrabKey
- grab keyboard keys
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;
- 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 keymask 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.
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 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
(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 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 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.
- 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
Window.
XAllowAccess(3X11)
, XGrabButton(3X11)
, XGrabKeyboard(3X11)
,
XGrabPointer(3X11)
Xlib - C Language X Interface
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