HelenOS sources

INET6_HOP_LIMIT_MAX  104 uspace/srv/net/inetsrv/icmpv6.c 	    INET6_HOP_LIMIT_MAX, 0);
INET6_HOP_LIMIT_MAX  205 uspace/srv/net/inetsrv/icmpv6.c 	    INET6_HOP_LIMIT_MAX, 0);
INET6_HOP_LIMIT_MAX   74 uspace/srv/net/inetsrv/ndp.c 	    IP_PROTO_ICMPV6, INET6_HOP_LIMIT_MAX, 0);
HelenOS homepage, sources at GitHub