set -- -x arg
opt=not
getopts x opt
r1=$? OPTIND1=$OPTIND opt1=$opt
: $(: $((OPTIND = 1)))
getopts x opt
r2=$? OPTIND2=$OPTIND
[ "$r1" = 0 ] && [ "$OPTIND1" = 2 ] && [ "$opt1" = x ] && [ "$r2" != 0 ] &&
	[ "$OPTIND2" = 2 ]