FM / bits

/usr/include/bits

Name	Size	Mode	Actions
types/	-	0755	rm
a.out.h	268	0644	edit dl rm
byteswap.h	2449	0644	edit dl rm
cmathcalls.h	4138	0644	edit dl rm
confname.h	23708	0644	edit dl rm
cpu-set.h	4515	0644	edit dl rm
dirent.h	1770	0644	edit dl rm
dlfcn.h	2520	0644	edit dl rm
elfclass.h	426	0644	edit dl rm
endian.h	176	0644	edit dl rm
environments.h	3790	0644	edit dl rm
epoll.h	1070	0644	edit dl rm
errno.h	1425	0644	edit dl rm
error.h	2683	0644	edit dl rm
eventfd.h	1128	0644	edit dl rm
fcntl-linux.h	13712	0644	edit dl rm
fcntl.h	2245	0644	edit dl rm
fcntl2.h	5574	0644	edit dl rm
fenv.h	4605	0644	edit dl rm
fenvinline.h	190	0644	edit dl rm
floatn-common.h	9764	0644	edit dl rm
floatn.h	4372	0644	edit dl rm
flt-eval-method.h	1214	0644	edit dl rm
fp-fast.h	1215	0644	edit dl rm
fp-logb.h	1011	0644	edit dl rm
getopt_core.h	3666	0644	edit dl rm
getopt_ext.h	3037	0644	edit dl rm
getopt_posix.h	1809	0644	edit dl rm
hwcap.h	971	0644	edit dl rm
in.h	9466	0644	edit dl rm
indirect-return.h	1585	0644	edit dl rm
initspin.h	25	0644	edit dl rm
inotify.h	1079	0644	edit dl rm
ioctl-types.h	2455	0644	edit dl rm
ioctls.h	4477	0644	edit dl rm
ipc.h	2070	0644	edit dl rm
ipctypes.h	1175	0644	edit dl rm
iscanonical.h	2478	0644	edit dl rm
libc-header-start.h	2607	0644	edit dl rm
libm-simd-decl-stubs.h	3003	0644	edit dl rm
link.h	4285	0644	edit dl rm
link_lavcurrent.h	1099	0644	edit dl rm
locale.h	1367	0644	edit dl rm
local_lim.h	3184	0644	edit dl rm
long-double.h	923	0644	edit dl rm
math-finite.h	5374	0644	edit dl rm
math-vector.h	2307	0644	edit dl rm
mathcalls-helper-functions.h	1764	0644	edit dl rm
mathcalls-narrow.h	1306	0644	edit dl rm
mathcalls.h	13100	0644	edit dl rm
mathdef.h	890	0644	edit dl rm
mathinline.h	13015	0644	edit dl rm
mman-linux.h	4895	0644	edit dl rm
mman-shared.h	2736	0644	edit dl rm
mman.h	2063	0644	edit dl rm
monetary-ldbl.h	1046	0644	edit dl rm
mqueue.h	1245	0644	edit dl rm
mqueue2.h	2150	0644	edit dl rm
msq.h	2637	0644	edit dl rm
netdb.h	1263	0644	edit dl rm
param.h	1432	0644	edit dl rm
poll.h	2075	0644	edit dl rm
poll2.h	2485	0644	edit dl rm
posix1_lim.h	5188	0644	edit dl rm
posix2_lim.h	2866	0644	edit dl rm
posix_opt.h	5766	0644	edit dl rm
printf-ldbl.h	991	0644	edit dl rm
pthreadtypes-arch.h	3290	0644	edit dl rm
pthreadtypes.h	3071	0644	edit dl rm
ptrace-shared.h	2900	0644	edit dl rm
resource.h	6298	0644	edit dl rm
sched.h	3747	0644	edit dl rm
select.h	2105	0644	edit dl rm
select2.h	1437	0644	edit dl rm
sem.h	2619	0644	edit dl rm
semaphore.h	1237	0644	edit dl rm
setjmp.h	1286	0644	edit dl rm
setjmp2.h	1704	0644	edit dl rm
shm.h	3591	0644	edit dl rm
sigaction.h	2934	0644	edit dl rm
sigcontext.h	4264	0644	edit dl rm
sigevent-consts.h	1470	0644	edit dl rm
siginfo-arch.h	729	0644	edit dl rm
siginfo-consts-arch.h	204	0644	edit dl rm
siginfo-consts.h	5973	0644	edit dl rm
signalfd.h	1066	0644	edit dl rm
signum-generic.h	4340	0644	edit dl rm
signum.h	1633	0644	edit dl rm
sigstack.h	1167	0644	edit dl rm
sigthread.h	1691	0644	edit dl rm
sockaddr.h	1513	0644	edit dl rm
socket.h	15562	0644	edit dl rm
socket2.h	3036	0644	edit dl rm
socket_type.h	2215	0644	edit dl rm
ss_flags.h	1187	0644	edit dl rm
stab.def	9039	0644	edit dl rm
stat.h	7619	0644	edit dl rm
statfs.h	1916	0644	edit dl rm
statvfs.h	3422	0644	edit dl rm
statx-generic.h	2049	0644	edit dl rm
statx.h	1399	0644	edit dl rm
stdint-intn.h	1036	0644	edit dl rm
stdint-uintn.h	1048	0644	edit dl rm
stdio-ldbl.h	3013	0644	edit dl rm
stdio.h	5586	0644	edit dl rm
stdio2.h	12546	0644	edit dl rm
stdio_lim.h	1212	0644	edit dl rm
stdlib-bsearch.h	1377	0644	edit dl rm
stdlib-float.h	1114	0644	edit dl rm
stdlib-ldbl.h	1372	0644	edit dl rm
stdlib.h	5069	0644	edit dl rm
strings_fortified.h	1239	0644	edit dl rm
string_fortified.h	4683	0644	edit dl rm
syscall.h	45663	0644	edit dl rm
sysctl.h	898	0644	edit dl rm
syslog-ldbl.h	1205	0644	edit dl rm
syslog-path.h	1060	0644	edit dl rm
syslog.h	1684	0644	edit dl rm
sysmacros.h	2952	0644	edit dl rm
sys_errlist.h	1215	0644	edit dl rm
termios.h	5363	0644	edit dl rm
thread-shared-types.h	6735	0644	edit dl rm
time.h	2998	0644	edit dl rm
timerfd.h	1102	0644	edit dl rm
timex.h	4595	0644	edit dl rm
types.h	8335	0644	edit dl rm
typesizes.h	3397	0644	edit dl rm
uintn-identity.h	1541	0644	edit dl rm
uio-ext.h	1922	0644	edit dl rm
uio_lim.h	1384	0644	edit dl rm
unistd.h	10812	0644	edit dl rm
utmp.h	4066	0644	edit dl rm
utmpx.h	3577	0644	edit dl rm
utsname.h	1212	0644	edit dl rm
waitflags.h	1696	0644	edit dl rm
waitstatus.h	2286	0644	edit dl rm
wchar-ldbl.h	2423	0644	edit dl rm
wchar.h	1905	0644	edit dl rm
wchar2.h	18221	0644	edit dl rm
wctype-wchar.h	6301	0644	edit dl rm
wordsize.h	442	0644	edit dl rm
xopen_lim.h	3857	0644	edit dl rm

Edit: /usr/include/bits/in.h (9466B)

/* Copyright (C) 1991-2018 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_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.  */

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