XkbSAGroup man page

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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