XGrabDeviceButton(3X11) X FUNCTIONS XGrabDeviceButton(3X11)
NAME
XGrabDeviceButton, XUngrabDeviceButton - grab/ungrab exten-
sion input device buttons
SYNTAX
int XGrabDeviceButton(Display *display, XDevice *device,
unsigned int button, unsigned int modifiers, XDevice
*modifier_device, Window grab_window, Bool
owner_events, unsigned int event_count, XEventClass
*event_list, int this_device_mode, int
other_devices_mode);
int XUngrabDeviceButton(Display *display, XDevice *device,
unsigned int button, unsigned int modifiers, XDevice
*modifier_device, Window grab_window);
ARGUMENTS
display Specifies the connection to the X server.
device Specifies the device that is to be grabbed or
released
button Specifies the device button that is to be
grabbed or released or AnyButton.
modifiers Specifies the set of keymasks or AnyModifier.
The mask is the bitwise inclusive OR of the
valid keymask bits. Valid bits are: Shiftmask,
LockMask, ControlMask, Mod1Mask, Mod2Mask,
Mod3Mask, Mod4Mask, Mod5Mask.
modifier_device
specifies the device whose modifiers are to be
used. If the modifier_device specified is NULL,
the X keyboard will be used as the
modifier_device.
grab_window Specifies the grab window.
owner_events
Specifies a Boolean value that indicates whether
the device events are to be reported as usual or
reported with respect to the grab window if
selected by the event list.
event_count Specifies the number of event classes in the
event list.
event_list Specifies which events are reported to the
client.
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XGrabDeviceButton(3X11) X FUNCTIONS XGrabDeviceButton(3X11)
this_device_mode
Specifies further processing of events from this
device. You can pass GrabModeSync or GrabMo-
deAsync.
other_devices_mode
Specifies further processing of events from all
other devices. You can pass GrabModeSync or
GrabModeAsync.
DESCRIPTION
The XGrabDeviceButton request establishes a passive grab. In
the future, the device is actively grabbed (as for XGrabDev-
ice, the last-grab time is set to the time at which the but-
ton was pressed (as transmitted in the DeviceButtonPress
event), and the DeviceButtonPress event is reported if all
of the following conditions are true:
+ The device is not grabbed, and the specified button is
logically pressed when the specified modifier keys are
logically down on the specified modifier device and no
other buttons or modifier keys are logically down.
+ Either the grab window is an ancestor of (or is) the
focus window, OR the grab window is a descendent of the
focus window and contains the device.
+ A passive grab on the same button/modifier combination
does not exist on any ancestor of grab_window.
The interpretation of the remaining arguments is as for
XGrabDevice. The active grab is terminated automatically
when the logical state of the device has all buttons
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.
This request overrides all previous grabs by the same client
on the same button/modifier combinations on the same window.
A modifiers of AnyModifier is equivalent to issuing the grab
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
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.
A modifier_device of NULL indicates that the X keyboard is
to be used as the modifier_device.
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XGrabDeviceButton(3X11) X FUNCTIONS XGrabDeviceButton(3X11)
If some other client has already issued a XGrabDeviceButton
with the same button/modifier combination on the same win-
dow, a BadAccess error results. When using AnyModifier or
AnyButton , the request fails completely, and a BadAccess
error results (no grabs are established) if there is a con-
flicting grab for any combination. XGrabDeviceButton has no
effect on an active grab.
XGrabDeviceButton can generate BadClass, BadDevice, Bad-
Match, BadValue, and BadWindow errors.
The XUngrabDeviceButton request releases the passive grab
for a button/modifier combination on the specified window if
it was grabbed by this client. A modifier of AnyModifier is
equivalent to issuing the ungrab request for all possible
modifier combinations, including the combination of no
modifiers. A button of AnyButton is equivalent to issuing
the request for all possible buttons. XUngrabDeviceButton
has no effect on an active grab.
A modifier_device of NULL indicates that the X keyboard
should be used as the modifier_device.
XUngrabDeviceButton can generate BadDevice, BadMatch, Bad-
Value and BadWindow errors.
DIAGNOSTICS
BadDevice An invalid device was specified. The specified
device does not exist or has not been opened by
this client via XOpenInputDevice. This error
may also occur if the specified device is the X
keyboard or X pointer device.
BadMatch This error may occur if an XGrabDeviceButton
request was made specifying a device that has no
buttons, or specifying a modifier device that
has no keys.
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.
SEE ALSO
XAllowDeviceEvents(3X),
XGrabDevice(3X),
XGrabDeviceKey(3X),
XFree86 Version 4.5.0 3
XGrabDeviceButton(3X11) X FUNCTIONS XGrabDeviceButton(3X11)
Programming With Xlib
XFree86 Version 4.5.0 4