XkbSelectEvents - Selects and / or deselects for delivery of one or more Xkb
events and has them delivered under all conditions
Bool
XkbSelectEvents (Display *display, unsigned int
device_spec, unsigned long int
bits_to_change, unsigned long int
values_for_bits);
- display
- connection to the X server
- device_spec
- device ID, or XkbUseCoreKbd
- bits_to_change
- determines events to be selected / deselected
- values_for_bits
- 1=>select, 0->deselect; for events in
bits_to_change
Xkb events are selected using an event mask, much the same as normal core X
events are selected. However, unlike selecting core X events, where you must
specify the selection status (on or off) for all possible event types whenever
you wish to change the selection criteria for any one event, Xkb allows you to
restrict the specification to only the event types you wish to change. This
means that you do not need to remember the event selection values for all
possible types each time you want to change one of them.
Many Xkb event types are generated under several different circumstances. When
selecting to receive an Xkb event, you may specify either that you want it
delivered under all circumstances, or that you want it delivered only for a
subset of the possible circumstances.
You can also deselect an event type that was previously selected for, using the
same granularity.
Xkb provides two functions to select and deselect delivery of Xkb events.
XkbSelectEvents allows you to select or deselect delivery of more than
one Xkb event type at once. Events selected using
XkbSelectEvents are
delivered to your program under all circumstances that generate the events. To
restrict delivery of an event to a subset of the conditions under which it
occurs, use
XkbSelectEventDetails. XkbSelectEventDetails only allows
you to change the selection conditions for a single event at a time, but it
provides a means of fine-tuning the conditions under which the event is
delivered.
This request changes the Xkb event selection mask for the keyboard specified by
device_spec.
Each Xkb event that can be selected is represented by a bit in the
bits_to_change and
values_for_bits masks. Only the event
selection bits specified by the
bits_to_change parameter are affected;
any unspecified bits are left unchanged. To turn on event selection for an
event, set the bit for the event in the
bits_to_change parameter and
set the corresponding bit in the
values_for_bits parameter. To turn off
event selection for an event, set the bit for the event in the
bits_to_change parameter and do not set the corresponding bit in the
values_for_bits parameter. The valid values for both of these
parameters are an inclusive bitwise OR of the masks shown in Table 1. There is
no interface to return your client's current event selection mask. Clients
cannot set other clients' event selection masks.
The X server reports the events defined by Xkb to your client application only
if you have requested them via a call to
XkbSelectEvents or
XkbSelectEventDetails. Specify the event types in which you are
interested in a mask.
Table 1 lists the event mask constants that can be specified with the
XkbSelectEvents request and the circumstances in which the mask should
be specified.
Table 1 XkbSelectEvents Mask Constants |
|
|
|
Event Mask |
Value |
Notification Wanted |
|
XkbNewKeyboardNotifyMask |
(1L<<0) |
Keyboard geometry change |
XkbMapNotifyMask |
(1L<<1) |
Keyboard mapping change |
XkbStateNotifyMask |
(1L<<2) |
Keyboard state change |
XkbControlsNotifyMask |
(1L<<3) |
Keyboard control change |
XkbIndicatorStateNotifyMask |
(1L<<4) |
Keyboard indicator state change |
XkbIndicatorMapNotifyMask |
(1L<<5) |
Keyboard indicator map change |
XkbNamesNotifyMask |
(1L<<6) |
Keyboard name change |
XkbCompatMapNotifyMask |
(1L<<7) |
Keyboard compat map change |
XkbBellNotifyMask |
(1L<<8) |
Bell |
XkbActionMessageMask |
(1L<<9) |
Action message |
XkbAccessXNotifyMask |
(1L<<10) |
AccessX features |
XkbExtensionDeviceNotifyMask |
(1L<<11) |
Extension device |
XkbAllEventsMask |
(0xFFF) |
All Xkb events |
If a bit is not set in the
bits_to_change parameter, but the
corresponding bit is set in the
values_for_bits parameter, a BadMatch
protocol error results. If an undefined bit is set in either the
bits_to_change or the
values_for_bits parameter, a BadValue
protocol error results.
All event selection bits are initially zero for clients using the Xkb extension.
Once you set some bits, they remain set for your client until you clear them
via another call to
XkbSelectEvents.
XkbSelectEvents returns False if the Xkb extension has not been
initialized and True otherwise.
- True
- The XkbSelectEvents function returns True if the Xkb
extension has been initialized.
- False
- The XkbSelectEvents function returns False if the
Xkb extension has not been initialized.
XkbSelectEventDetails(3),
XkbUseCoreKbd(3)