bionic (3) XkbSetBounceKeysDelay.3.gz
NAME
XkbSetBounceKeysDelay - Sets the BounceKeys delay for a keyboard device
SYNOPSIS
Bool XkbSetBounceKeysDelay (Display *display, unsigned int device_spec, unsigned int *delay);
ARGUMENTS
- display
connection to X server
- device_spec
device ID, or XkbUseCoreKbd
- delay
backfilled with bounce keys delay, ms
DESCRIPTION
The server can generate XkbAccessXNotify events for some of the global keyboard controls. The detail
field describes what AccessX event just occurred and can be any of the values in Table 1.
Table 1 AccessXNotify Events
─────────────────────────────────────────────────────────────
detail Reason
─────────────────────────────────────────────────────────────
XkbAXN_SKPress A key was pressed when SlowKeys was
enabled.
XkbAXN_SKAccept A key was accepted (held longer than the
SlowKeys delay).
XkbAXN_SKRelease An accepted SlowKeys key was released.
XkbAXN_SKReject A key was rejected (released before the
SlowKeys delay expired).
XkbAXN_BKAccept A key was accepted by BounceKeys.
XkbAXN_BKReject A key was rejected (pressed before the
BounceKeys delay expired).
XkbAXN_AXKWarning AccessXKeys is about to turn on/off
StickyKeys or BounceKeys.
The keycode field reports the keycode of the key for which the event occurred. If the action is related
to SlowKeys, the slowKeysDelay field contains the current SlowKeys acceptance delay. If the action is
related to BounceKeys, the debounceDelay field contains the current BounceKeys debounce delay.
Selecting for AccessX Events
To receive XkbAccessXNotify events under all possible conditions, use XkbSelectEvents and pass
XkbAccesXNotifyMask in both bits_to_change and values_for_bits.
To receive XkbStateNotify events only under certain conditions, use XkbSelectEventDetails using
XkbAccessXNotify as the event_type and specifying the desired state changes in bits_to_change and
values_for_bits using mask bits from Table 2.
Table 2 AccessXNotify Event Details
─────────────────────────────────────────────────────────────────────────
XkbAccessXNotify Event Details Value Circumstances
─────────────────────────────────────────────────────────────────────────
XkbAXN_SKPressMask (1<<0) Slow key press notification
wanted
XkbAXN_SKAcceptMask (1<<1) Slow key accept notification
wanted
XkbAXN_SKRejectMask (1<<2) Slow key reject notification
wanted
XkbAXN_SKReleaseMask (1<<3) Slow key release notification
wanted
XkbAXN_BKAcceptMask (1<<4) Bounce key accept notification
wanted
XkbAXN_BKRejectMask (1<<5) Bounce key reject notification
wanted
XkbAXN_AXKWarningMask (1<<6) AccessX warning notification
wanted
XkbAllAccessXEventsMask (0x7f) All AccessX features
notifications wanted
Some users may accidentally "bounce" on a key when they release it. They press it once, then accidentally
press it again after they release it. The BounceKeys control temporarily disables a key after it has been
pressed, effectively "debouncing" the keyboard. The period of time the key is disabled after it is
released is known as the BounceKeys delay. BounceKeys is a boolean control.
When the BounceKeys control is active, the server reports acceptance or rejection of any key to
interested clients by sending an appropriate AccessXNotify event.
XkbSetBounceKeysDelay sends a request to configure the BounceKeys control to the server. It does not wait
for a reply and normally returns True. Specifying a value of zero for the delay parameter causes
XkbSetBounceKeysDelay to generate a BadValue protocol error. If a compatible version of the Xkb extension
is not available in the server, XkbSetBounceKeysDelay returns False.
RETURN VALUES
True The XkbSetBounceKeysDelay function returns True when it sends a request to configure the
BounceKeys control to the server.
False The XkbSetBounceKeysDelay function returns False if a compatible version of the Xkb
extension is not available in the server.
STRUCTURES
The structure for the XkbAccessXNotify event type is as follows:
typedef struct {
int type; /∗ Xkb extension base event code */
unsigned long serial; /∗ X server serial number for event */
Bool send_event; /∗ True => synthetically generated */
Display * display; /∗ server connection where event generated */
Time time; /∗ server time when event generated */
int xkb_type; /∗ XkbAccessXNotify */
int device; /∗ Xkb device ID, will not be XkbUseCoreKbd
*/
int detail; /∗ XkbAXN_* */
KeyCode keycode; /∗ key of event */
int slowKeysDelay; /∗ current SlowKeys delay */
int debounceDelay; /∗ current debounce delay */
} XkbAccessXNotifyEvent;
DIAGNOSTICS
BadValue An argument is out of range