The XkbControlsChangesRec structure allows applications to track modifications to an XkbControlsRec structure and thereby reduce the amount of traffic sent to the server. The same XkbControlsChangesRec structure may be used in several successive modifications to the same XkbControlsRec structure, then subsequently used to cause all of the changes, and only the changes, to be propagated to the server.
The changed_ctrls field is a mask specifying which logical sets of data in the controls structure have been modified. In this context, modified means set, that is, if a value is set to the same value it previously contained, it has still been modified, and is noted as changed. Valid values for changed_ctrls are any combination of the masks listed in Table 1 that have "ok" in the changed_ctrls column. Setting a bit implies the corresponding data fields from the "Relevant XkbControlsRec Data Fields" column in Table 1 have been modified. The enabled_ctrls_changes field specifies which bits in the enabled_ctrls field have changed. If the number of keyboard groups has changed, the num_groups_changed field is set to True.
Table 1 shows the actual values for the individual mask bits used to select controls for modification and to enable and disable the control. Note that the same mask bit is used to specify general modifications to the parameters used to configure the control (which), and to enable and disable the control (enabled_ctrls). The anomalies in the table (no "ok" in column) are for controls that have no configurable attributes; and for controls that are not boolean controls and therefore cannot be enabled or disabled.
| Table 1 Xkb Controls |
| Control Control |
| Selection Relevant |
| Mask XkbControlsRec Boolean Control |
| (which parameter) DataFields enabled_ctrls bit Section |
| _ |
| AccessXFeedback |
| XkbAccessXFeedbackMask |
| T} ax_options: T{ |
| XkbAccessXFeedbackMask |
| T} 10.6.3 |
| XkbAX_*FBMask |
| AccessXKeys |
| XkbAccessXKeysMask |
| T} 10.6.1 |
| AccessXTimeout |
| XkbAccessXTimeoutMask |
| T} ax_timeout T{ |
| XkbAccessXTimeoutMask |
| T} 10.6.2 |
| axt_opts_mask |
| axt_opts_values |
| axt_ctrls_mask |
| axt_ctrls_values |
| AudibleBell |
| XkbAudibleBellMask |
| T} 9.2 |
| AutoReset |
| BounceKeys |
| XkbBounceKeysMask |
| T} debounce_delay T{ |
| XkbBounceKeysMask |
| T} 10.6.7 |
| Detectable- |
| Autorepeat |
| EnabledControls |
| XkbControlsEnabledMask |
| T} enabled_ctrls T{ |
| Non-Boolean Control |
| T} 10.1.1 |
| GroupsWrap |
| XkbGroupsWrapMask |
| T} groups_wrap T{ |
| Non-Boolean Control |
| T} 10.7.1 |
| IgnoreGroupLock |
| XkbIgnoreGroupLockMask |
| T} 10.7.3 |
| IgnoreLockMods |
| XkbIgnoreLockModsMask |
| T} ignore_lock T{ |
| Non-Boolean Control |
| T} 5.1 |
| InternalMods |
| XkbInternalModsMask |
| T} internal T{ |
| Non-Boolean Control |
| T} 5.1 |
| MouseKeys |
| XkbMouseKeysMask |
| T} mk_dflt_btn T{ |
| XkbMouseKeysMask |
| T} 10.5.1 |
| MouseKeysAccel |
| XkbMouseKeysAccelMask |
| T} mk_delay T{ |
| XkbMouseKeysAccelMask |
| T} 10.5.2 |
| mk_interval |
| mk_time_to_max |
| mk_max_speed |
| mk_curve |
| Overlay1 |
| XkbOverlay1Mask |
| T} 10.4 |
| Overlay2 |
| XkbOverlay2Mask |
| T} 10.4 |
| PerKeyRepeat |
| XkbPerKeyRepeatMask |
| T} per_key_repeat T{ |
| Non-Boolean Control |
| T} 10.3.1 |
| RepeatKeys |
| XkbRepeatKeysMask |
| T} repeat_delay T{ |
| XkbRepeatKeysMask |
| T} 10.3 |
| repeat_interval |
| SlowKeys |
| XkbSlowKeysMask |
| T} slow_keys_delay T{ |
| XkbSlowKeysMask |
| T} 10.6.6 |
| StickyKeys |
| XkbStickyKeysMask |
| T} ax_options: T{ |
| XkbStickyKeysMask |
| T} 10.6.8 |
| XkbAX_TwoKeysMask |
| XkbAX_LatchToLockMask |
Table 2 shows the actual values for the individual mask bits used to select controls for modification and to enable and disable the control. Note that the same mask bit is used to specify general modifications to the parameters used to configure the control (which), and to enable and disable the control (enabled_ctrls). The anomalies in the table (no "ok" in column) are for controls that have no configurable attributes; and for controls that are not boolean controls and therefore cannot be enabled or disabled.
| Table 2 Controls Mask Bits |
| Mask Bit which or enabled Value |
| changed_ctrls _ctrls |
| XkbRepeatKeysMask ok ok (1L<<0) |
| XkbSlowKeysMask ok ok (1L<<1) |
| XkbBounceKeysMask ok ok (1L<<2) |
| XkbStickyKeysMask ok ok (1L<<3) |
| XkbMouseKeysMask ok ok (1L<<4) |
| XkbMouseKeysAccelMask ok ok (1L<<5) |
| XkbAccessXKeysMask ok ok (1L<<6) |
| XkbAccessXTimeoutMask ok ok (1L<<7) |
| XkbAccessXFeedbackMask ok ok (1L<<8) |
| XkbAudibleBellMask ok (1L<<9) |
| XkbOverlay1Mask ok (1L<<10) |
| XkbOverlay2Mask ok (1L<<11) |
| XkbIgnoreGroupLockMask ok (1L<<12) |
| XkbGroupsWrapMask ok (1L<<27) |
| XkbInternalModsMask ok (1L<<28) |
| XkbIgnoreLockModsMask ok (1L<<29) |
| XkbPerKeyRepeatMask ok (1L<<30) |
| XkbControlsEnabledMask ok (1L<<31) |
| XkbAccessXOptionsMask ok ok (XkbStickyKeysMask | |
| XkbAccessXFeedbackMask) |
| XkbAllBooleanCtrlsMask ok (0x00001FFF) |
| XkbAllControlsMask ok (0xF8001FFF) |
If you have an Xkb description with controls that have been modified and an XkbControlsChangesRec that describes the changes that have been made, the XkbChangeControls function provides a flexible method for updating the controls in a server to match those in the changed keyboard description.
XkbChangeControls copies any controls fields specified by changes from the keyboard description controls structure, xkb->ctrls, to the server specified by dpy.
The XkbControlsChangesRec structure is defined
as follows:
typedef struct _XkbControlsChanges {
unsigned int changed_ctrls; /* bits indicating changed control
data
*/
unsigned int enabled_ctrls_changes; /* bits indicating enabled/disabled
controls */
Bool num_groups_changed; /* True if number of keyboard
groups
changed */
} XkbControlsChangesRec,*XkbControlsChangesPtr;