XkbSAGroup − Returns the group_XXX field of act converted to a signed int
| int XkbSAGroup | (XkbAction act); | 
| − act | action from which to extract group | 
XkbSAGroup returns the group_XXX field of act converted to a signed int.
Actions associated with the XkbGroupAction structure change the current group state when keys are pressed and released:
    typedef struct _XkbGroupAction {
        unsigned char    type;       /∗ XkbSA_{Set|Latch|Lock}Group */
        unsigned char    flags;      /∗ with type, controls the effect on groups
*/
        char             group_XXX;  /∗ represents a group index or delta */
    } XkbGroupAction;
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