In environments where computers are shared, features such as SlowKeys present a problem: if SlowKeys is on, the keyboard can appear to be unresponsive because keys are not accepted until they are held for a certain period of time. To help solve this problem, Xkb provides an AccessXTimeout control to automatically change the enabled/disabled state of any boolean controls and to change the value of the AccessXKeys and AccessXFeedback control attributes if the keyboard is idle for a specified period of time.
When a timeout as specified by AccessXTimeout occurs and a control is consequently modified, Xkb generates an XkbControlsNotify event.
XkbGetAccessXTimeout sends a request to the X server to obtain the current values for the AccessXTimeout attributes, waits for a reply, and backfills the values into the appropriate arguments. The parameters options_mask_rtrn and options_values_rtrn are backfilled with the options to modify and the values for ax_options, which is a field in the XkbControlsRec structure. XkbGetAccessXTimeout returns True if successful; if a compatible version of the Xkb extension is not available in the server, XkbGetAccessXTimeout returns False.
The XkbControlsRec structure is defined as follows:
#define XkbMaxLegalKeyCode 255
#define XkbPerKeyBitArraySize ((XkbMaxLegalKeyCode+1)/8)
typedef struct {
unsigned char mk_dflt_btn; /* default button for keyboard driven
mouse */
unsigned char num_groups; /* number of keyboard groups */
unsigned char groups_wrap; /* how to wrap out-of-bounds groups
*/
XkbModsRec internal; /* defines server internal modifiers
*/
XkbModsRec ignore_lock; /* modifiers to ignore when checking
for grab */
unsigned int enabled_ctrls; /* 1 bit => corresponding boolean
control enabled */
unsigned short repeat_delay; /* ms delay until first repeat */
unsigned short repeat_interval; /* ms delay between repeats */
unsigned short slow_keys_delay; /* ms minimum time key must be down
to be ok */
unsigned short debounce_delay; /* ms delay before key reactivated
*/
unsigned short mk_delay; /* ms delay to second mouse motion
event */
unsigned short mk_interval; /* ms delay between repeat mouse
events */
unsigned short mk_time_to_max; /* # intervals until constant mouse
move */
unsigned short mk_max_speed; /* multiplier for maximum mouse speed
*/
short mk_curve; /* determines mouse move curve type
*/
unsigned short ax_options; /* 1 bit => Access X option enabled
*/
unsigned short ax_timeout; /* seconds until Access X disabled
*/
unsigned short axt_opts_mask; /* 1 bit => options to reset on Access
X timeout */
unsigned short axt_opts_values; /* 1 bit => turn option on, 0=> off
*/
unsigned int axt_ctrls_mask; /* which bits in enabled_ctrls to
modify */
unsigned int axt_ctrls_values; /* values for new bits in enabled_ctrls
*/
unsigned char per_key_repeat[XkbPerKeyBitArraySize]; /* per key
auto repeat */
} XkbControlsRec, *XkbControlsPtr;