Actions associated with the XkbCtrlsAction structure change the state of the boolean controls.
The type field can have any one of the values shown in Table 1.
| Table 1 Controls Action Types | |
| Type | Effect | 
| XkbSA_SetControls | A key press enables any boolean controls specified in the ctrls fields that were 
not already enabled at 
the time of the key press.
A key release disables any controls enabled by the key press.
This action can cause XkbControlsNotify events. | 
| XkbSA_LockControls | If the XkbSA_LockNoLock bit is not set in the flags field, a key press enables 
any controls specified in 
the ctrls fields that were not already enabled at the time of the key press. If the XkbSA_LockNoUnlock bit is not set in the flags field, a key release disables any controls specified in the ctrls fields that were not already disabled at the time of the key press. This action can cause XkbControlsNotify events. | 
The flags field is composed of the bitwise inclusive OR of the masks shown in Table 2.
| Table 2 Control Action Flags | |
| Flag | Meaning | 
| XkbSA_LockNoLock | If set, and the action type is XkbSA_LockControls, the server only disables 
controls. | 
| XkbSA_LockNoUnlock | If set, and the action type is XkbSA_LockControls, the server only enables 
controls. | 
The XkbSA_SetControls action implements a key that enables a boolean control when pressed and disables it when released. The XkbSA_LockControls action is used to implement a key that toggles the state of a boolean control each time it is pressed and released. The XkbSA_LockNoLock and XkbSA_LockNoUnlock flags allow modifying the toggling behavior to only unlock or only lock the boolean control.
The ctrls0, ctrls1, ctrls2, and ctrls3 fields represent the boolean controls in the enabled_ctrls field of the controls structure. Xkb macros, to convert between the two formats.
XkbSAActionSetCtrls sets the ctrls0 through ctrls3 fields of act from ctrls.
    typedef struct _XkbCtrlsAction {
        unsigned char    type;    /* XkbSA_SetControls, XkbSA_LockControls */
        unsigned char    flags;   /* with type, controls enabling and disabling 
of controls */
        unsigned char    ctrls3;  /* ctrls0 through ctrls3 represent the boolean 
controls */
        unsigned char    ctrls2;  /* ctrls0 through ctrls3 represent the boolean 
controls */
        unsigned char    ctrls1;  /* ctrls0 through ctrls3 represent the boolean 
controls */
        unsigned char    ctrls0;  /* ctrls0 through ctrls3 represent the boolean 
controls */
    } XkbCtrlsAction;