Provided by: libx11-doc_1.8.10-2_all 

NAME
XkbSASetGroup - Sets the group_XXX field of act from the group index grp
SYNOPSIS
void XkbSASetGroup (XkbAction act, int grp);
ARGUMENTS
act action from which to set group
grp group index to set in group_XXX
DESCRIPTION
XkbSASetGroup sets the group_XXX field of act from the group index grp.
STRUCTURE
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;
WARNING
This manpage seems to be incomplete
X Version 11 libX11 1.8.10 XkbSASetGroup(3)