Symbol: IPV6_V6ONLY
usr/src/boot/include/netinet6/in6.h
418
#define IPV6_V6ONLY 27 /* bool; make AF_INET6 sockets v6 only */
usr/src/uts/common/netinet/in.h
1271
#define IPV6_V6ONLY 0x27 /* v6 only socket option */