XGrabButton(3X11) XLIB FUNCTIONS XGrabButton(3X11)NAME
XGrabButton, XUngrabButton - grab pointer buttons
SYNTAX
XGrabButton(display, button, modifiers, grab_window,
owner_events, event_mask,
pointer_mode, keyboard_mode, confine_to,
cursor)
Display *display;
unsigned int button;
unsigned int modifiers;
Window grab_window;
Bool owner_events;
unsigned int event_mask;
int pointer_mode, keyboard_mode;
Window confine_to;
Cursor cursor;
XUngrabButton(display, button, modifiers, grab_window)
Display *display;
unsigned int button;
unsigned int modifiers;
Window grab_window;
ARGUMENTS
button Specifies the pointer button that is to be
grabbed or released or AnyButton.
confine_to
Specifies the window to confine the pointer in
or None.
cursor Specifies the cursor that is to be displayed or
None.
display Specifies the connection to the X server.
event_mask
Specifies which pointer events are reported to
the client. The mask is the bitwise inclusive
OR of the valid pointer event mask bits.
grab_window
Specifies the grab window.
keyboard_mode
Specifies further processing of keyboard events.
You can pass GrabModeSync or GrabModeAsync.
modifiers Specifies the set of keymasks or AnyModifier.
The mask is the bitwise inclusive OR of the
valid keymask bits.
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XGrabButton(3X11) XLIB FUNCTIONS XGrabButton(3X11)
owner_events
Specifies a Boolean value that indicates whether
the pointer events are to be reported as usual
or reported with respect to the grab window if
selected by the event mask.
pointer_mode
Specifies further processing of pointer events.
You can pass GrabModeSync or GrabModeAsync.
DESCRIPTION
The XGrabButton function establishes a passive grab. In
the future, the pointer is actively grabbed (as for
XGrabPointer), the last-pointer-grab time is set to the
time at which the button was pressed (as transmitted in
the ButtonPress event), and the ButtonPress event is
reported if all of the following conditions are true:
o The pointer is not grabbed, and the specified button
is logically pressed when the specified modifier keys
are logically down, and no other buttons or modifier
keys are logically down.
o The grab_window contains the pointer.
o The confine_to window (if any) is viewable.
o A passive grab on the same button/key combination
does not exist on any ancestor of grab_window.
The interpretation of the remaining arguments is as for
XGrabPointer. The active grab is terminated automatically
when the logical state of the pointer has all buttons
released (independent of the state of the logical 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.
This request overrides all previous grabs by the same
client on the same button/key combinations on the same
window. A modifiers of AnyModifier is equivalent to issu-
ing the grab request for all possible modifier combina-
tions (including the combination of no modifiers). It is
not required that all modifiers specified have currently
assigned KeyCodes. A button of AnyButton is equivalent to
issuing the request for all possible buttons. Otherwise,
it is not required that the specified button currently be
assigned to a physical button.
If some other client has already issued a XGrabButton with
the same button/key combination on the same window, a
BadAccess error results. When using AnyModifier or
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XGrabButton(3X11) XLIB FUNCTIONS XGrabButton(3X11)
AnyButton, the request fails completely, and a BadAccess
error results (no grabs are established) if there is a
conflicting grab for any combination. XGrabButton has no
effect on an active grab.
XGrabButton can generate BadCursor, BadValue, and BadWin-
dow errors.
The XUngrabButton function releases the passive button/key
combination on the specified window if it was grabbed by
this client. A modifiers of AnyModifier is equivalent to
issuing the ungrab request for all possible modifier com-
binations, including the combination of no modifiers. A
button of AnyButton is equivalent to issuing the request
for all possible buttons. XUngrabButton has no effect on
an active grab.
XUngrabButton can generate BadValue and BadWindow errors.
DIAGNOSTICS
BadCursor A value for a Cursor argument does not name a
defined Cursor.
BadValue Some numeric value falls outside the range of
values accepted by the request. Unless a spe-
cific 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.
SEE ALSOXAllowEvents(3X11), XGrabPointer(3X11), XGrabKey(3X11),
XGrabKeyboard(3X11),
Xlib - C Language X Interface
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