XkbSetControls man page
XkbSetControls — Copies changes to the X server based on a modified ctrls structure in a local copy of the keyboard description
Bool XkbSetControls (Display *display, unsigned long which, XkbDescPtr xkb);
- - display
connection to X server
- - which
mask of controls requested
- - xkb
keyboard description for controls information
For each bit that is set in the which parameter, XkbSetControls sends the corresponding values from the xkb->ctrls field to the server. Valid values for which are any combination of the masks listed in Table 1 that have "ok" in the which column.
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 Controls Mask Bits|
|Mask Bit||which or||enabled||Value|
If xkb->ctrls is NULL, the server does not support a compatible version of Xkb, or the Xkb extension has not been properly initialized, XkbSetControls returns False. Otherwise, it sends the request to the X server and returns True.
Note that changes to attributes of controls in the XkbControlsRec structure are apparent only when the associated control is enabled, although the corresponding values are still updated in the X server. For example, the repeat_delay and repeat_interval fields are ignored unless the RepeatKeys control is enabled (that is, the X server's equivalent of xkb->ctrls has XkbRepeatKeyMask set in enabled_ctrls). It is permissible to modify the attributes of a control in one call to XkbSetControls and enable the control in a subsequent call. See XkbChangeEnabledControls for more information on enabling and disabling controls.
Note that the enabled_ctrls field is itself a control - the EnabledControls control. As such, to set a specific configuration of enabled and disabled boolean controls, you must set enabled_ctrls to the appropriate bits to enable only the controls you want and disable all others, then specify the XkbControlsEnabledMask in a call to XkbSetControls.
Because this is somewhat awkward if all you want to do is enable and disable controls, and not modify any of their attributes, a convenience function is also provided for this purpose, XkbChangeEnabledControls.
The XkbSetControls function returns True when it sends the request to the X server.
The XkbSetControls function returns False when xkb->ctrls is NULL, the server does not support a compatible version of Xkb, or the Xkb extension has not been properly initialized.
Unable to allocate storage
A compatible version of Xkb was not available in the server or an argument has correct type and range, but is otherwise invalid
XkbAllocDeviceLedInfo(3), XkbSetIgnoreLockMods(3), XkbSetServerInternalMods(3).