LIST_LEFT
&s[LIST_LEFT], &s[LIST_RIGHT], &s[AFTER],
&s[LIST_LEFT], &s[LIST_RIGHT], &s[AFTER],
&s[LIST_LEFT], &s[LIST_RIGHT], &s[AFTER],
&s[LIST_LEFT], &s[LIST_RIGHT], &s[AFTER],
if (s[LIST_LEFT].cx != 0) /* already have marker */
current = LIST_LEFT;