XGRABDEVICEBUTTON(3) libXi XGRABDEVICEBUTTON(3)NAME
XGrabDeviceButton, XUngrabDeviceButton - grab/ungrab extension input
device buttons
SYNTAX
#include <X11/extensions/XInput.h>
int XGrabDeviceButton(Display *display, XDevice *device,
unsigned int button, unsigned int modifiers,
XDevice*modifier_device, Window grab_window,
Boolowner_events, unsigned int event_count,
XEventClass*event_list, int this_device_mode,
intother_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_devicespecified 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 deviceevents
are to be reported as usual or reported with respect to the grab
windowif 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.
this_device_mode
Specifies further processing of events from this device.You can pass
GrabModeSync or GrabModeAsync.
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 XGrabDevice, the
last-grab time is set to the time at which the button 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. Theactive grab is terminated automatically when the logical state of the devicehas all buttons released (independent of the logical state of the modifierkeys).Note that the logical state of a device (as seen by client applications) maylag the physical state if device event processing is frozen.This request overrides all previous grabs by the same client on the samebutton/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 isequivalent to issuing the request for all possible buttons. Otherwise, it is
not required that the specified button currently be assigned to a physicalbutton.A modifier_device of NULL indicates that the X keyboard is to be used as themodifier_device.If some other client has already issued a XGrabDeviceButton with the samebutton/modifier combination on the same window, 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 conflictinggrab for any combination. XGrabDeviceButton has no effect on an active grab.XGrabDeviceButton can generate BadClass, BadDevice, BadMatch, BadValue, and
BadWindow errors..P The XUngrabDeviceButton request releases the passive grabfor a button/modifier combination on the specified window if it was grabbed by
this client. A modifier of AnyModifier is equivalent to issuing the ungrabrequest for all possible modifier combinations, including the combination of
no modifiers. A button of AnyButton is equivalent to issuing the request forall possible buttons. XUngrabDeviceButton has no effect on an active grab.A modifier_device of NULL indicates that the X keyboard should be used as themodifier_device.XUngrabDeviceButton can generate BadDevice, BadMatch, BadValue 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 ALSOXAllowDeviceEvents(3), XGrabDevice(3), XGrabDeviceKey(3)
03/04/2009 XGRABDEVICEBUTTON(3)