The C and C++ Include Header Files

/usr/include/x86_64-linux-gnu/bits/in.h


$ cat -n /usr/include/x86_64-linux-gnu/bits/in.h

     1	/* Copyright (C) 1991-2024 Free Software Foundation, Inc.
     2	   This file is part of the GNU C Library.
     3	
     4	   The GNU C Library is free software; you can redistribute it and/or
     5	   modify it under the terms of the GNU Lesser General Public
     6	   License as published by the Free Software Foundation; either
     7	   version 2.1 of the License, or (at your option) any later version.
     8	
     9	   The GNU C Library is distributed in the hope that it will be useful,
    10	   but WITHOUT ANY WARRANTY; without even the implied warranty of
    11	   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    12	   Lesser General Public License for more details.
    13	
    14	   You should have received a copy of the GNU Lesser General Public
    15	   License along with the GNU C Library; if not, see
    16	   <https://www.gnu.org/licenses/>.  */
    17	
    18	/* Linux version.  */
    19	
    20	#ifndef _NETINET_IN_H
    21	# error "Never use <bits/in.h> directly; include <netinet/in.h> instead."
    22	#endif
    23	
    24	/* If the application has already included linux/in6.h from a linux-based
    25	   kernel then we will not define the IPv6 IPPROTO_* defines, in6_addr (nor the
    26	   defines), sockaddr_in6, or ipv6_mreq. Same for in6_ptkinfo or ip6_mtuinfo
    27	   in linux/ipv6.h. The ABI used by the linux-kernel and glibc match exactly.
    28	   Neither the linux kernel nor glibc should break this ABI without coordination.
    29	   In upstream kernel 56c176c9 the _UAPI prefix was stripped so we need to check
    30	   for _LINUX_IN6_H and _IPV6_H now, and keep checking the old versions for
    31	   maximum backwards compatibility.  */
    32	#if defined _UAPI_LINUX_IN6_H \
    33	    || defined _UAPI_IPV6_H \
    34	    || defined _LINUX_IN6_H \
    35	    || defined _IPV6_H
    36	/* This is not quite the same API since the kernel always defines s6_addr16 and
    37	   s6_addr32. This is not a violation of POSIX since POSIX says "at least the
    38	   following member" and that holds true.  */
    39	# define __USE_KERNEL_IPV6_DEFS 1
    40	#else
    41	# define __USE_KERNEL_IPV6_DEFS 0
    42	#endif
    43	
    44	/* Options for use with `getsockopt' and `setsockopt' at the IP level.
    45	   The first word in the comment at the right is the data type used;
    46	   "bool" means a boolean value stored in an `int'.  */
    47	#define        IP_OPTIONS      4       /* ip_opts; IP per-packet options.  */
    48	#define        IP_HDRINCL      3       /* int; Header is included with data.  */
    49	#define        IP_TOS          1       /* int; IP type of service and precedence.  */
    50	#define        IP_TTL          2       /* int; IP time to live.  */
    51	#define        IP_RECVOPTS     6       /* bool; Receive all IP options w/datagram.  */
    52	/* For BSD compatibility.  */
    53	#define        IP_RECVRETOPTS  IP_RETOPTS       /* bool; Receive IP options for response.  */
    54	#define        IP_RETOPTS      7       /* ip_opts; Set/get IP per-packet options.  */
    55	#define IP_MULTICAST_IF 32	/* in_addr; set/get IP multicast i/f */
    56	#define IP_MULTICAST_TTL 33	/* unsigned char; set/get IP multicast ttl */
    57	#define IP_MULTICAST_LOOP 34	/* bool; set/get IP multicast loopback */
    58	#define IP_ADD_MEMBERSHIP 35	/* ip_mreq; add an IP group membership */
    59	#define IP_DROP_MEMBERSHIP 36	/* ip_mreq; drop an IP group membership */
    60	#define IP_UNBLOCK_SOURCE 37	/* ip_mreq_source: unblock data from source */
    61	#define IP_BLOCK_SOURCE 38	/* ip_mreq_source: block data from source */
    62	#define IP_ADD_SOURCE_MEMBERSHIP 39 /* ip_mreq_source: join source group */
    63	#define IP_DROP_SOURCE_MEMBERSHIP 40 /* ip_mreq_source: leave source group */
    64	#define IP_MSFILTER 41
    65	#ifdef __USE_MISC
    66	# define MCAST_JOIN_GROUP 42	/* group_req: join any-source group */
    67	# define MCAST_BLOCK_SOURCE 43	/* group_source_req: block from given group */
    68	# define MCAST_UNBLOCK_SOURCE 44 /* group_source_req: unblock from given group*/
    69	# define MCAST_LEAVE_GROUP 45	/* group_req: leave any-source group */
    70	# define MCAST_JOIN_SOURCE_GROUP 46 /* group_source_req: join source-spec gr */
    71	# define MCAST_LEAVE_SOURCE_GROUP 47 /* group_source_req: leave source-spec gr*/
    72	# define MCAST_MSFILTER 48
    73	# define IP_MULTICAST_ALL 49
    74	# define IP_UNICAST_IF 50
    75	
    76	# define MCAST_EXCLUDE   0
    77	# define MCAST_INCLUDE   1
    78	#endif
    79	
    80	#define IP_ROUTER_ALERT	5	/* bool */
    81	#define IP_PKTINFO	8	/* bool */
    82	#define IP_PKTOPTIONS	9
    83	#define IP_PMTUDISC	10	/* obsolete name? */
    84	#define IP_MTU_DISCOVER	10	/* int; see below */
    85	#define IP_RECVERR	11	/* bool */
    86	#define IP_RECVTTL	12	/* bool */
    87	#define IP_RECVTOS	13	/* bool */
    88	#define IP_MTU		14	/* int */
    89	#define IP_FREEBIND	15
    90	#define IP_IPSEC_POLICY 16
    91	#define IP_XFRM_POLICY	17
    92	#define IP_PASSSEC	18
    93	#define IP_TRANSPARENT	19
    94	#define IP_MULTICAST_ALL 49	/* bool */
    95	
    96	/* TProxy original addresses */
    97	#define IP_ORIGDSTADDR       20
    98	#define IP_RECVORIGDSTADDR   IP_ORIGDSTADDR
    99	
   100	#define IP_MINTTL       21
   101	#define IP_NODEFRAG     22
   102	#define IP_CHECKSUM     23
   103	#define IP_BIND_ADDRESS_NO_PORT 24
   104	#define IP_RECVFRAGSIZE 25
   105	#define IP_RECVERR_RFC4884 26
   106	
   107	/* IP_MTU_DISCOVER arguments.  */
   108	#define IP_PMTUDISC_DONT   0	/* Never send DF frames.  */
   109	#define IP_PMTUDISC_WANT   1	/* Use per route hints.  */
   110	#define IP_PMTUDISC_DO     2	/* Always DF.  */
   111	#define IP_PMTUDISC_PROBE  3	/* Ignore dst pmtu.  */
   112	/* Always use interface mtu (ignores dst pmtu) but don't set DF flag.
   113	   Also incoming ICMP frag_needed notifications will be ignored on
   114	   this socket to prevent accepting spoofed ones.  */
   115	#define IP_PMTUDISC_INTERFACE           4
   116	/* Like IP_PMTUDISC_INTERFACE but allow packets to be fragmented.  */
   117	#define IP_PMTUDISC_OMIT		5
   118	
   119	#define IP_MULTICAST_IF			32
   120	#define IP_MULTICAST_TTL 		33
   121	#define IP_MULTICAST_LOOP 		34
   122	#define IP_ADD_MEMBERSHIP		35
   123	#define IP_DROP_MEMBERSHIP		36
   124	#define IP_UNBLOCK_SOURCE		37
   125	#define IP_BLOCK_SOURCE			38
   126	#define IP_ADD_SOURCE_MEMBERSHIP	39
   127	#define IP_DROP_SOURCE_MEMBERSHIP	40
   128	#define IP_MSFILTER			41
   129	#define IP_MULTICAST_ALL		49
   130	#define IP_UNICAST_IF			50
   131	#define IP_LOCAL_PORT_RANGE		51
   132	#define IP_PROTOCOL			52
   133	
   134	/* To select the IP level.  */
   135	#define SOL_IP	0
   136	
   137	#define IP_DEFAULT_MULTICAST_TTL        1
   138	#define IP_DEFAULT_MULTICAST_LOOP       1
   139	#define IP_MAX_MEMBERSHIPS              20
   140	
   141	#ifdef __USE_MISC
   142	/* Structure used to describe IP options for IP_OPTIONS and IP_RETOPTS.
   143	   The `ip_dst' field is used for the first-hop gateway when using a
   144	   source route (this gets put into the header proper).  */
   145	struct ip_opts
   146	  {
   147	    struct in_addr ip_dst;	/* First hop; zero without source route.  */
   148	    char ip_opts[40];		/* Actually variable in size.  */
   149	  };
   150	
   151	/* Structure used for IP_PKTINFO.  */
   152	struct in_pktinfo
   153	  {
   154	    int ipi_ifindex;			/* Interface index  */
   155	    struct in_addr ipi_spec_dst;	/* Routing destination address  */
   156	    struct in_addr ipi_addr;		/* Header destination address  */
   157	  };
   158	#endif
   159	
   160	/* Options for use with `getsockopt' and `setsockopt' at the IPv6 level.
   161	   The first word in the comment at the right is the data type used;
   162	   "bool" means a boolean value stored in an `int'.  */
   163	#define IPV6_ADDRFORM		1
   164	#define IPV6_2292PKTINFO	2
   165	#define IPV6_2292HOPOPTS	3
   166	#define IPV6_2292DSTOPTS	4
   167	#define IPV6_2292RTHDR		5
   168	#define IPV6_2292PKTOPTIONS	6
   169	#define IPV6_CHECKSUM		7
   170	#define IPV6_2292HOPLIMIT	8
   171	
   172	#define SCM_SRCRT		IPV6_RXSRCRT
   173	
   174	#define IPV6_NEXTHOP		9
   175	#define IPV6_AUTHHDR		10
   176	#define IPV6_UNICAST_HOPS	16
   177	#define IPV6_MULTICAST_IF	17
   178	#define IPV6_MULTICAST_HOPS	18
   179	#define IPV6_MULTICAST_LOOP	19
   180	#define IPV6_JOIN_GROUP		20
   181	#define IPV6_LEAVE_GROUP	21
   182	#define IPV6_ROUTER_ALERT	22
   183	#define IPV6_MTU_DISCOVER	23
   184	#define IPV6_MTU		24
   185	#define IPV6_RECVERR		25
   186	#define IPV6_V6ONLY		26
   187	#define IPV6_JOIN_ANYCAST	27
   188	#define IPV6_LEAVE_ANYCAST	28
   189	#define IPV6_MULTICAST_ALL	29
   190	#define IPV6_ROUTER_ALERT_ISOLATE 30
   191	#define IPV6_RECVERR_RFC4884	31
   192	#define IPV6_IPSEC_POLICY	34
   193	#define IPV6_XFRM_POLICY	35
   194	#define IPV6_HDRINCL		36
   195	
   196	/* Advanced API (RFC3542) (1).  */
   197	#define IPV6_RECVPKTINFO	49
   198	#define IPV6_PKTINFO		50
   199	#define IPV6_RECVHOPLIMIT	51
   200	#define IPV6_HOPLIMIT		52
   201	#define IPV6_RECVHOPOPTS	53
   202	#define IPV6_HOPOPTS		54
   203	#define IPV6_RTHDRDSTOPTS	55
   204	#define IPV6_RECVRTHDR		56
   205	#define IPV6_RTHDR		57
   206	#define IPV6_RECVDSTOPTS	58
   207	#define IPV6_DSTOPTS		59
   208	#define IPV6_RECVPATHMTU	60
   209	#define IPV6_PATHMTU		61
   210	#define IPV6_DONTFRAG		62
   211	
   212	/* Advanced API (RFC3542) (2).  */
   213	#define IPV6_RECVTCLASS		66
   214	#define IPV6_TCLASS		67
   215	
   216	#define IPV6_AUTOFLOWLABEL	70
   217	
   218	/* RFC5014.  */
   219	#define IPV6_ADDR_PREFERENCES	72
   220	
   221	/* RFC5082.  */
   222	#define IPV6_MINHOPCOUNT	73
   223	
   224	#define IPV6_ORIGDSTADDR	74
   225	#define IPV6_RECVORIGDSTADDR	IPV6_ORIGDSTADDR
   226	#define IPV6_TRANSPARENT	75
   227	#define IPV6_UNICAST_IF		76
   228	#define IPV6_RECVFRAGSIZE	77
   229	#define IPV6_FREEBIND		78
   230	
   231	/* Obsolete synonyms for the above.  */
   232	#if !__USE_KERNEL_IPV6_DEFS
   233	# define IPV6_ADD_MEMBERSHIP	IPV6_JOIN_GROUP
   234	# define IPV6_DROP_MEMBERSHIP	IPV6_LEAVE_GROUP
   235	#endif
   236	#define IPV6_RXHOPOPTS		IPV6_HOPOPTS
   237	#define IPV6_RXDSTOPTS		IPV6_DSTOPTS
   238	
   239	/* IPV6_MTU_DISCOVER values.  */
   240	#define IPV6_PMTUDISC_DONT	0	/* Never send DF frames.  */
   241	#define IPV6_PMTUDISC_WANT	1	/* Use per route hints.  */
   242	#define IPV6_PMTUDISC_DO	2	/* Always DF.  */
   243	#define IPV6_PMTUDISC_PROBE	3	/* Ignore dst pmtu.  */
   244	#define IPV6_PMTUDISC_INTERFACE	4	/* See IP_PMTUDISC_INTERFACE.  */
   245	#define IPV6_PMTUDISC_OMIT	5	/* See IP_PMTUDISC_OMIT.  */
   246	
   247	/* Socket level values for IPv6.  */
   248	#define SOL_IPV6        41
   249	#define SOL_ICMPV6      58
   250	
   251	/* Routing header options for IPv6.  */
   252	#define IPV6_RTHDR_LOOSE	0	/* Hop doesn't need to be neighbour. */
   253	#define IPV6_RTHDR_STRICT	1	/* Hop must be a neighbour.  */
   254	
   255	#define IPV6_RTHDR_TYPE_0	0	/* IPv6 Routing header type 0.  */