aarch64-linux-gnu-9.2/aarch64-none-linux-gnu/libc/usr/include/bits/in.h - toolchains/linux-x86/gcc - Git at Google

 /* Copyright (C) 1991-2019 Free Software Foundation, Inc.
    This file is part of the GNU C Library.

    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    The GNU C Library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */

 /* Linux version.  */

 #ifndef _NETINET_IN_H
 # error "Never use <bits/in.h> directly; include <netinet/in.h> instead."
 #endif

 /* If the application has already included linux/in6.h from a linux-based
    kernel then we will not define the IPv6 IPPROTO_* defines, in6_addr (nor the
    defines), sockaddr_in6, or ipv6_mreq. Same for in6_ptkinfo or ip6_mtuinfo
    in linux/ipv6.h. The ABI used by the linux-kernel and glibc match exactly.
    Neither the linux kernel nor glibc should break this ABI without coordination.
    In upstream kernel 56c176c9 the _UAPI prefix was stripped so we need to check
    for _LINUX_IN6_H and _IPV6_H now, and keep checking the old versions for
    maximum backwards compatibility.  */
 #if defined _UAPI_LINUX_IN6_H \
     || defined _UAPI_IPV6_H \
     || defined _LINUX_IN6_H \
     || defined _IPV6_H
 /* This is not quite the same API since the kernel always defines s6_addr16 and
    s6_addr32. This is not a violation of POSIX since POSIX says "at least the
    following member" and that holds true.  */
 # define __USE_KERNEL_IPV6_DEFS 1
 #else
 # define __USE_KERNEL_IPV6_DEFS 0
 #endif

 /* Options for use with `getsockopt' and `setsockopt' at the IP level.
    The first word in the comment at the right is the data type used;
    "bool" means a boolean value stored in an `int'.  */
 #define        IP_OPTIONS      4       /* ip_opts; IP per-packet options.  */
 #define        IP_HDRINCL      3       /* int; Header is included with data.  */
 #define        IP_TOS          1       /* int; IP type of service and precedence.  */
 #define        IP_TTL          2       /* int; IP time to live.  */
 #define        IP_RECVOPTS     6       /* bool; Receive all IP options w/datagram.  */
 /* For BSD compatibility.  */
 #define        IP_RECVRETOPTS  IP_RETOPTS       /* bool; Receive IP options for response.  */
 #define        IP_RETOPTS      7       /* ip_opts; Set/get IP per-packet options.  */
 #define IP_MULTICAST_IF 32	/* in_addr; set/get IP multicast i/f */
 #define IP_MULTICAST_TTL 33	/* unsigned char; set/get IP multicast ttl */
 #define IP_MULTICAST_LOOP 34	/* bool; set/get IP multicast loopback */
 #define IP_ADD_MEMBERSHIP 35	/* ip_mreq; add an IP group membership */
 #define IP_DROP_MEMBERSHIP 36	/* ip_mreq; drop an IP group membership */
 #define IP_UNBLOCK_SOURCE 37	/* ip_mreq_source: unblock data from source */
 #define IP_BLOCK_SOURCE 38	/* ip_mreq_source: block data from source */
 #define IP_ADD_SOURCE_MEMBERSHIP 39 /* ip_mreq_source: join source group */
 #define IP_DROP_SOURCE_MEMBERSHIP 40 /* ip_mreq_source: leave source group */
 #define IP_MSFILTER 41
 #ifdef __USE_MISC
 # define MCAST_JOIN_GROUP 42	/* group_req: join any-source group */
 # define MCAST_BLOCK_SOURCE 43	/* group_source_req: block from given group */
 # define MCAST_UNBLOCK_SOURCE 44 /* group_source_req: unblock from given group*/
 # define MCAST_LEAVE_GROUP 45	/* group_req: leave any-source group */
 # define MCAST_JOIN_SOURCE_GROUP 46 /* group_source_req: join source-spec gr */
 # define MCAST_LEAVE_SOURCE_GROUP 47 /* group_source_req: leave source-spec gr*/
 # define MCAST_MSFILTER 48
 # define IP_MULTICAST_ALL 49
 # define IP_UNICAST_IF 50

 # define MCAST_EXCLUDE   0
 # define MCAST_INCLUDE   1
 #endif

 #define IP_ROUTER_ALERT	5	/* bool */
 #define IP_PKTINFO	8	/* bool */
 #define IP_PKTOPTIONS	9
 #define IP_PMTUDISC	10	/* obsolete name? */
 #define IP_MTU_DISCOVER	10	/* int; see below */
 #define IP_RECVERR	11	/* bool */
 #define IP_RECVTTL	12	/* bool */
 #define IP_RECVTOS	13	/* bool */
 #define IP_MTU		14	/* int */
 #define IP_FREEBIND	15
 #define IP_IPSEC_POLICY 16
 #define IP_XFRM_POLICY	17
 #define IP_PASSSEC	18
 #define IP_TRANSPARENT	19
 #define IP_MULTICAST_ALL 49	/* bool */

 /* TProxy original addresses */
 #define IP_ORIGDSTADDR       20
 #define IP_RECVORIGDSTADDR   IP_ORIGDSTADDR

 #define IP_MINTTL       21
 #define IP_NODEFRAG     22
 #define IP_CHECKSUM     23
 #define IP_BIND_ADDRESS_NO_PORT 24
 #define IP_RECVFRAGSIZE 25

 /* IP_MTU_DISCOVER arguments.  */
 #define IP_PMTUDISC_DONT   0	/* Never send DF frames.  */
 #define IP_PMTUDISC_WANT   1	/* Use per route hints.  */
 #define IP_PMTUDISC_DO     2	/* Always DF.  */
 #define IP_PMTUDISC_PROBE  3	/* Ignore dst pmtu.  */
 /* Always use interface mtu (ignores dst pmtu) but don't set DF flag.
    Also incoming ICMP frag_needed notifications will be ignored on
    this socket to prevent accepting spoofed ones.  */
 #define IP_PMTUDISC_INTERFACE           4
 /* Like IP_PMTUDISC_INTERFACE but allow packets to be fragmented.  */
 #define IP_PMTUDISC_OMIT		5

 #define IP_MULTICAST_IF			32
 #define IP_MULTICAST_TTL 		33
 #define IP_MULTICAST_LOOP 		34
 #define IP_ADD_MEMBERSHIP		35
 #define IP_DROP_MEMBERSHIP		36
 #define IP_UNBLOCK_SOURCE		37
 #define IP_BLOCK_SOURCE			38
 #define IP_ADD_SOURCE_MEMBERSHIP	39
 #define IP_DROP_SOURCE_MEMBERSHIP	40
 #define IP_MSFILTER			41
 #define IP_MULTICAST_ALL		49
 #define IP_UNICAST_IF			50

 /* To select the IP level.  */
 #define SOL_IP	0

 #define IP_DEFAULT_MULTICAST_TTL        1
 #define IP_DEFAULT_MULTICAST_LOOP       1
 #define IP_MAX_MEMBERSHIPS              20

 #ifdef __USE_MISC
 /* Structure used to describe IP options for IP_OPTIONS and IP_RETOPTS.
    The `ip_dst' field is used for the first-hop gateway when using a
    source route (this gets put into the header proper).  */
 struct ip_opts
   {
     struct in_addr ip_dst;	/* First hop; zero without source route.  */
     char ip_opts[40];		/* Actually variable in size.  */
   };

 /* Like `struct ip_mreq' but including interface specification by index.  */
 struct ip_mreqn
   {
     struct in_addr imr_multiaddr;	/* IP multicast address of group */
     struct in_addr imr_address;		/* local IP address of interface */
     int	imr_ifindex;			/* Interface index */
   };

 /* Structure used for IP_PKTINFO.  */
 struct in_pktinfo
   {
     int ipi_ifindex;			/* Interface index  */
     struct in_addr ipi_spec_dst;	/* Routing destination address  */
     struct in_addr ipi_addr;		/* Header destination address  */
   };
 #endif

 /* Options for use with `getsockopt' and `setsockopt' at the IPv6 level.
    The first word in the comment at the right is the data type used;
    "bool" means a boolean value stored in an `int'.  */
 #define IPV6_ADDRFORM		1
 #define IPV6_2292PKTINFO	2
 #define IPV6_2292HOPOPTS	3
 #define IPV6_2292DSTOPTS	4
 #define IPV6_2292RTHDR		5
 #define IPV6_2292PKTOPTIONS	6
 #define IPV6_CHECKSUM		7
 #define IPV6_2292HOPLIMIT	8

 #define SCM_SRCRT		IPV6_RXSRCRT

 #define IPV6_NEXTHOP		9
 #define IPV6_AUTHHDR		10
 #define IPV6_UNICAST_HOPS	16
 #define IPV6_MULTICAST_IF	17
 #define IPV6_MULTICAST_HOPS	18
 #define IPV6_MULTICAST_LOOP	19
 #define IPV6_JOIN_GROUP		20
 #define IPV6_LEAVE_GROUP	21
 #define IPV6_ROUTER_ALERT	22
 #define IPV6_MTU_DISCOVER	23
 #define IPV6_MTU		24
 #define IPV6_RECVERR		25
 #define IPV6_V6ONLY		26
 #define IPV6_JOIN_ANYCAST	27
 #define IPV6_LEAVE_ANYCAST	28
 #define IPV6_MULTICAST_ALL	29
 #define IPV6_ROUTER_ALERT_ISOLATE 30
 #define IPV6_IPSEC_POLICY	34
 #define IPV6_XFRM_POLICY	35
 #define IPV6_HDRINCL		36

 /* Advanced API (RFC3542) (1).  */
 #define IPV6_RECVPKTINFO	49
 #define IPV6_PKTINFO		50
 #define IPV6_RECVHOPLIMIT	51
 #define IPV6_HOPLIMIT		52
 #define IPV6_RECVHOPOPTS	53
 #define IPV6_HOPOPTS		54
 #define IPV6_RTHDRDSTOPTS	55
 #define IPV6_RECVRTHDR		56
 #define IPV6_RTHDR		57
 #define IPV6_RECVDSTOPTS	58
 #define IPV6_DSTOPTS		59
 #define IPV6_RECVPATHMTU	60
 #define IPV6_PATHMTU		61
 #define IPV6_DONTFRAG		62

 /* Advanced API (RFC3542) (2).  */
 #define IPV6_RECVTCLASS		66
 #define IPV6_TCLASS		67

 #define IPV6_AUTOFLOWLABEL	70

 /* RFC5014.  */
 #define IPV6_ADDR_PREFERENCES	72

 /* RFC5082.  */
 #define IPV6_MINHOPCOUNT	73

 #define IPV6_ORIGDSTADDR	74
 #define IPV6_RECVORIGDSTADDR	IPV6_ORIGDSTADDR
 #define IPV6_TRANSPARENT	75
 #define IPV6_UNICAST_IF		76
 #define IPV6_RECVFRAGSIZE	77
 #define IPV6_FREEBIND		78

 /* Obsolete synonyms for the above.  */
 #if !__USE_KERNEL_IPV6_DEFS
 # define IPV6_ADD_MEMBERSHIP	IPV6_JOIN_GROUP
 # define IPV6_DROP_MEMBERSHIP	IPV6_LEAVE_GROUP
 #endif
 #define IPV6_RXHOPOPTS		IPV6_HOPOPTS
 #define IPV6_RXDSTOPTS		IPV6_DSTOPTS

 /* IPV6_MTU_DISCOVER values.  */
 #define IPV6_PMTUDISC_DONT	0	/* Never send DF frames.  */
 #define IPV6_PMTUDISC_WANT	1	/* Use per route hints.  */
 #define IPV6_PMTUDISC_DO	2	/* Always DF.  */
 #define IPV6_PMTUDISC_PROBE	3	/* Ignore dst pmtu.  */
 #define IPV6_PMTUDISC_INTERFACE	4	/* See IP_PMTUDISC_INTERFACE.  */
 #define IPV6_PMTUDISC_OMIT	5	/* See IP_PMTUDISC_OMIT.  */

 /* Socket level values for IPv6.  */
 #define SOL_IPV6        41
 #define SOL_ICMPV6      58

 /* Routing header options for IPv6.  */
 #define IPV6_RTHDR_LOOSE	0	/* Hop doesn't need to be neighbour. */
 #define IPV6_RTHDR_STRICT	1	/* Hop must be a neighbour.  */

 #define IPV6_RTHDR_TYPE_0	0	/* IPv6 Routing header type 0.  */
	/* Copyright (C) 1991-2019 Free Software Foundation, Inc.
	This file is part of the GNU C Library.

	The GNU C Library is free software; you can redistribute it and/or
	modify it under the terms of the GNU Lesser General Public
	License as published by the Free Software Foundation; either
	version 2.1 of the License, or (at your option) any later version.

	The GNU C Library is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public
	License along with the GNU C Library; if not, see
	<http://www.gnu.org/licenses/>. */

	/* Linux version. */

	#ifndef _NETINET_IN_H
	# error "Never use <bits/in.h> directly; include <netinet/in.h> instead."
	#endif

	/* If the application has already included linux/in6.h from a linux-based
	kernel then we will not define the IPv6 IPPROTO_* defines, in6_addr (nor the
	defines), sockaddr_in6, or ipv6_mreq. Same for in6_ptkinfo or ip6_mtuinfo
	in linux/ipv6.h. The ABI used by the linux-kernel and glibc match exactly.
	Neither the linux kernel nor glibc should break this ABI without coordination.
	In upstream kernel 56c176c9 the _UAPI prefix was stripped so we need to check
	for _LINUX_IN6_H and _IPV6_H now, and keep checking the old versions for
	maximum backwards compatibility. */
	#if defined _UAPI_LINUX_IN6_H \
	\|\| defined _UAPI_IPV6_H \
	\|\| defined _LINUX_IN6_H \
	\|\| defined _IPV6_H
	/* This is not quite the same API since the kernel always defines s6_addr16 and
	s6_addr32. This is not a violation of POSIX since POSIX says "at least the
	following member" and that holds true. */
	# define __USE_KERNEL_IPV6_DEFS 1
	#else
	# define __USE_KERNEL_IPV6_DEFS 0
	#endif

	/* Options for use with `getsockopt' and `setsockopt' at the IP level.
	The first word in the comment at the right is the data type used;
	"bool" means a boolean value stored in an `int'. */
	#define IP_OPTIONS 4 /* ip_opts; IP per-packet options. */
	#define IP_HDRINCL 3 /* int; Header is included with data. */
	#define IP_TOS 1 /* int; IP type of service and precedence. */
	#define IP_TTL 2 /* int; IP time to live. */
	#define IP_RECVOPTS 6 /* bool; Receive all IP options w/datagram. */
	/* For BSD compatibility. */
	#define IP_RECVRETOPTS IP_RETOPTS /* bool; Receive IP options for response. */
	#define IP_RETOPTS 7 /* ip_opts; Set/get IP per-packet options. */
	#define IP_MULTICAST_IF 32 /* in_addr; set/get IP multicast i/f */
	#define IP_MULTICAST_TTL 33 /* unsigned char; set/get IP multicast ttl */
	#define IP_MULTICAST_LOOP 34 /* bool; set/get IP multicast loopback */
	#define IP_ADD_MEMBERSHIP 35 /* ip_mreq; add an IP group membership */
	#define IP_DROP_MEMBERSHIP 36 /* ip_mreq; drop an IP group membership */
	#define IP_UNBLOCK_SOURCE 37 /* ip_mreq_source: unblock data from source */
	#define IP_BLOCK_SOURCE 38 /* ip_mreq_source: block data from source */
	#define IP_ADD_SOURCE_MEMBERSHIP 39 /* ip_mreq_source: join source group */
	#define IP_DROP_SOURCE_MEMBERSHIP 40 /* ip_mreq_source: leave source group */
	#define IP_MSFILTER 41
	#ifdef __USE_MISC
	# define MCAST_JOIN_GROUP 42 /* group_req: join any-source group */
	# define MCAST_BLOCK_SOURCE 43 /* group_source_req: block from given group */
	# define MCAST_UNBLOCK_SOURCE 44 /* group_source_req: unblock from given group*/
	# define MCAST_LEAVE_GROUP 45 /* group_req: leave any-source group */
	# define MCAST_JOIN_SOURCE_GROUP 46 /* group_source_req: join source-spec gr */
	# define MCAST_LEAVE_SOURCE_GROUP 47 /* group_source_req: leave source-spec gr*/
	# define MCAST_MSFILTER 48
	# define IP_MULTICAST_ALL 49
	# define IP_UNICAST_IF 50

	# define MCAST_EXCLUDE 0
	# define MCAST_INCLUDE 1
	#endif

	#define IP_ROUTER_ALERT 5 /* bool */
	#define IP_PKTINFO 8 /* bool */
	#define IP_PKTOPTIONS 9
	#define IP_PMTUDISC 10 /* obsolete name? */
	#define IP_MTU_DISCOVER 10 /* int; see below */
	#define IP_RECVERR 11 /* bool */
	#define IP_RECVTTL 12 /* bool */
	#define IP_RECVTOS 13 /* bool */
	#define IP_MTU 14 /* int */
	#define IP_FREEBIND 15
	#define IP_IPSEC_POLICY 16
	#define IP_XFRM_POLICY 17
	#define IP_PASSSEC 18
	#define IP_TRANSPARENT 19
	#define IP_MULTICAST_ALL 49 /* bool */

	/* TProxy original addresses */
	#define IP_ORIGDSTADDR 20
	#define IP_RECVORIGDSTADDR IP_ORIGDSTADDR

	#define IP_MINTTL 21
	#define IP_NODEFRAG 22
	#define IP_CHECKSUM 23
	#define IP_BIND_ADDRESS_NO_PORT 24
	#define IP_RECVFRAGSIZE 25

	/* IP_MTU_DISCOVER arguments. */
	#define IP_PMTUDISC_DONT 0 /* Never send DF frames. */
	#define IP_PMTUDISC_WANT 1 /* Use per route hints. */
	#define IP_PMTUDISC_DO 2 /* Always DF. */
	#define IP_PMTUDISC_PROBE 3 /* Ignore dst pmtu. */
	/* Always use interface mtu (ignores dst pmtu) but don't set DF flag.
	Also incoming ICMP frag_needed notifications will be ignored on
	this socket to prevent accepting spoofed ones. */
	#define IP_PMTUDISC_INTERFACE 4
	/* Like IP_PMTUDISC_INTERFACE but allow packets to be fragmented. */
	#define IP_PMTUDISC_OMIT 5

	#define IP_MULTICAST_IF 32
	#define IP_MULTICAST_TTL 33
	#define IP_MULTICAST_LOOP 34
	#define IP_ADD_MEMBERSHIP 35
	#define IP_DROP_MEMBERSHIP 36
	#define IP_UNBLOCK_SOURCE 37
	#define IP_BLOCK_SOURCE 38
	#define IP_ADD_SOURCE_MEMBERSHIP 39
	#define IP_DROP_SOURCE_MEMBERSHIP 40
	#define IP_MSFILTER 41
	#define IP_MULTICAST_ALL 49
	#define IP_UNICAST_IF 50

	/* To select the IP level. */
	#define SOL_IP 0

	#define IP_DEFAULT_MULTICAST_TTL 1
	#define IP_DEFAULT_MULTICAST_LOOP 1
	#define IP_MAX_MEMBERSHIPS 20

	#ifdef __USE_MISC
	/* Structure used to describe IP options for IP_OPTIONS and IP_RETOPTS.
	The `ip_dst' field is used for the first-hop gateway when using a
	source route (this gets put into the header proper). */
	struct ip_opts
	{
	struct in_addr ip_dst; /* First hop; zero without source route. */
	char ip_opts[40]; /* Actually variable in size. */
	};

	/* Like `struct ip_mreq' but including interface specification by index. */
	struct ip_mreqn
	{
	struct in_addr imr_multiaddr; /* IP multicast address of group */
	struct in_addr imr_address; /* local IP address of interface */
	int imr_ifindex; /* Interface index */
	};

	/* Structure used for IP_PKTINFO. */
	struct in_pktinfo
	{
	int ipi_ifindex; /* Interface index */
	struct in_addr ipi_spec_dst; /* Routing destination address */
	struct in_addr ipi_addr; /* Header destination address */
	};
	#endif

	/* Options for use with `getsockopt' and `setsockopt' at the IPv6 level.
	The first word in the comment at the right is the data type used;
	"bool" means a boolean value stored in an `int'. */
	#define IPV6_ADDRFORM 1
	#define IPV6_2292PKTINFO 2
	#define IPV6_2292HOPOPTS 3
	#define IPV6_2292DSTOPTS 4
	#define IPV6_2292RTHDR 5
	#define IPV6_2292PKTOPTIONS 6
	#define IPV6_CHECKSUM 7
	#define IPV6_2292HOPLIMIT 8

	#define SCM_SRCRT IPV6_RXSRCRT

	#define IPV6_NEXTHOP 9
	#define IPV6_AUTHHDR 10
	#define IPV6_UNICAST_HOPS 16
	#define IPV6_MULTICAST_IF 17
	#define IPV6_MULTICAST_HOPS 18
	#define IPV6_MULTICAST_LOOP 19
	#define IPV6_JOIN_GROUP 20
	#define IPV6_LEAVE_GROUP 21
	#define IPV6_ROUTER_ALERT 22
	#define IPV6_MTU_DISCOVER 23
	#define IPV6_MTU 24
	#define IPV6_RECVERR 25
	#define IPV6_V6ONLY 26
	#define IPV6_JOIN_ANYCAST 27
	#define IPV6_LEAVE_ANYCAST 28
	#define IPV6_MULTICAST_ALL 29
	#define IPV6_ROUTER_ALERT_ISOLATE 30
	#define IPV6_IPSEC_POLICY 34
	#define IPV6_XFRM_POLICY 35
	#define IPV6_HDRINCL 36

	/* Advanced API (RFC3542) (1). */
	#define IPV6_RECVPKTINFO 49
	#define IPV6_PKTINFO 50
	#define IPV6_RECVHOPLIMIT 51
	#define IPV6_HOPLIMIT 52
	#define IPV6_RECVHOPOPTS 53
	#define IPV6_HOPOPTS 54
	#define IPV6_RTHDRDSTOPTS 55
	#define IPV6_RECVRTHDR 56
	#define IPV6_RTHDR 57
	#define IPV6_RECVDSTOPTS 58
	#define IPV6_DSTOPTS 59
	#define IPV6_RECVPATHMTU 60
	#define IPV6_PATHMTU 61
	#define IPV6_DONTFRAG 62

	/* Advanced API (RFC3542) (2). */
	#define IPV6_RECVTCLASS 66
	#define IPV6_TCLASS 67

	#define IPV6_AUTOFLOWLABEL 70

	/* RFC5014. */
	#define IPV6_ADDR_PREFERENCES 72

	/* RFC5082. */
	#define IPV6_MINHOPCOUNT 73

	#define IPV6_ORIGDSTADDR 74
	#define IPV6_RECVORIGDSTADDR IPV6_ORIGDSTADDR
	#define IPV6_TRANSPARENT 75
	#define IPV6_UNICAST_IF 76
	#define IPV6_RECVFRAGSIZE 77
	#define IPV6_FREEBIND 78

	/* Obsolete synonyms for the above. */
	#if !__USE_KERNEL_IPV6_DEFS
	# define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
	# define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
	#endif
	#define IPV6_RXHOPOPTS IPV6_HOPOPTS
	#define IPV6_RXDSTOPTS IPV6_DSTOPTS

	/* IPV6_MTU_DISCOVER values. */
	#define IPV6_PMTUDISC_DONT 0 /* Never send DF frames. */
	#define IPV6_PMTUDISC_WANT 1 /* Use per route hints. */
	#define IPV6_PMTUDISC_DO 2 /* Always DF. */
	#define IPV6_PMTUDISC_PROBE 3 /* Ignore dst pmtu. */
	#define IPV6_PMTUDISC_INTERFACE 4 /* See IP_PMTUDISC_INTERFACE. */
	#define IPV6_PMTUDISC_OMIT 5 /* See IP_PMTUDISC_OMIT. */

	/* Socket level values for IPv6. */
	#define SOL_IPV6 41
	#define SOL_ICMPV6 58

	/* Routing header options for IPv6. */
	#define IPV6_RTHDR_LOOSE 0 /* Hop doesn't need to be neighbour. */
	#define IPV6_RTHDR_STRICT 1 /* Hop must be a neighbour. */

	#define IPV6_RTHDR_TYPE_0 0 /* IPv6 Routing header type 0. */