XGrabDeviceButton(3X11) X Version 11(Release 5) XGrabDeviceButton(3X11)
NAME
XGrabDeviceButton, XUngrabDeviceButton - grab/ungrab extension input
device buttons
SYNTAX
XGrabDeviceButton(display, device, button, modifiers, modifier_device, grab_window,
owner_events, event_count, event_list, this_device_mode, other_devices_mode)
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, other_devices_mode;
XUngrabDeviceButton(display, device, button, modifiers, modifier_device, grab_window)
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.
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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. 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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If some other client has already issued a XGrabDeviceButton with the same
button/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 conflicting grab for any combination. XGrabDeviceButton has
no effect on an active grab.
XGrabDeviceButton can generate BadClass, BadDevice, BadMatch, 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, 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 ALSO
XAllowDeviceEvents(3X),
XGrabDevice(3X),
XGrabDeviceKey(3X),
Programming With Xlib
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