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/posix_opt.h (5766B)

/* Define POSIX options for Linux.
   Copyright (C) 1996-2018 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; see the file COPYING.LIB.  If
   not, see <http://www.gnu.org/licenses/>.  */

#ifndef	_BITS_POSIX_OPT_H
#define	_BITS_POSIX_OPT_H	1

/* Job control is supported.  */
#define	_POSIX_JOB_CONTROL	1

/* Processes have a saved set-user-ID and a saved set-group-ID.  */
#define	_POSIX_SAVED_IDS	1

/* Priority scheduling is supported.  */
#define	_POSIX_PRIORITY_SCHEDULING	200809L

/* Synchronizing file data is supported.  */
#define	_POSIX_SYNCHRONIZED_IO	200809L

/* The fsync function is present.  */
#define	_POSIX_FSYNC	200809L

/* Mapping of files to memory is supported.  */
#define	_POSIX_MAPPED_FILES	200809L

/* Locking of all memory is supported.  */
#define	_POSIX_MEMLOCK	200809L

/* Locking of ranges of memory is supported.  */
#define	_POSIX_MEMLOCK_RANGE	200809L

/* Setting of memory protections is supported.  */
#define	_POSIX_MEMORY_PROTECTION	200809L

/* Some filesystems allow all users to change file ownership.  */
#define	_POSIX_CHOWN_RESTRICTED	0

/* `c_cc' member of 'struct termios' structure can be disabled by
   using the value _POSIX_VDISABLE.  */
#define	_POSIX_VDISABLE	'\0'

/* Filenames are not silently truncated.  */
#define	_POSIX_NO_TRUNC	1

/* X/Open realtime support is available.  */
#define _XOPEN_REALTIME	1

/* X/Open thread realtime support is available.  */
#define _XOPEN_REALTIME_THREADS	1

/* XPG4.2 shared memory is supported.  */
#define	_XOPEN_SHM	1

/* Tell we have POSIX threads.  */
#define _POSIX_THREADS	200809L

/* We have the reentrant functions described in POSIX.  */
#define _POSIX_REENTRANT_FUNCTIONS      1
#define _POSIX_THREAD_SAFE_FUNCTIONS	200809L

/* We provide priority scheduling for threads.  */
#define _POSIX_THREAD_PRIORITY_SCHEDULING	200809L

/* We support user-defined stack sizes.  */
#define _POSIX_THREAD_ATTR_STACKSIZE	200809L

/* We support user-defined stacks.  */
#define _POSIX_THREAD_ATTR_STACKADDR	200809L

/* We support priority inheritence.  */
#define _POSIX_THREAD_PRIO_INHERIT	200809L

/* We support priority protection, though only for non-robust
   mutexes.  */
#define _POSIX_THREAD_PRIO_PROTECT	200809L

#ifdef __USE_XOPEN2K8
/* We support priority inheritence for robust mutexes.  */
# define _POSIX_THREAD_ROBUST_PRIO_INHERIT	200809L

/* We do not support priority protection for robust mutexes.  */
# define _POSIX_THREAD_ROBUST_PRIO_PROTECT	-1
#endif

/* We support POSIX.1b semaphores.  */
#define _POSIX_SEMAPHORES	200809L

/* Real-time signals are supported.  */
#define _POSIX_REALTIME_SIGNALS	200809L

/* We support asynchronous I/O.  */
#define _POSIX_ASYNCHRONOUS_IO	200809L
#define _POSIX_ASYNC_IO		1
/* Alternative name for Unix98.  */
#define _LFS_ASYNCHRONOUS_IO	1
/* Support for prioritization is also available.  */
#define _POSIX_PRIORITIZED_IO	200809L

/* The LFS support in asynchronous I/O is also available.  */
#define _LFS64_ASYNCHRONOUS_IO	1

/* The rest of the LFS is also available.  */
#define _LFS_LARGEFILE		1
#define _LFS64_LARGEFILE	1
#define _LFS64_STDIO		1

/* POSIX shared memory objects are implemented.  */
#define _POSIX_SHARED_MEMORY_OBJECTS	200809L

/* CPU-time clocks support needs to be checked at runtime.  */
#define _POSIX_CPUTIME	0

/* Clock support in threads must be also checked at runtime.  */
#define _POSIX_THREAD_CPUTIME	0

/* GNU libc provides regular expression handling.  */
#define _POSIX_REGEXP	1

/* Reader/Writer locks are available.  */
#define _POSIX_READER_WRITER_LOCKS	200809L

/* We have a POSIX shell.  */
#define _POSIX_SHELL	1

/* We support the Timeouts option.  */
#define _POSIX_TIMEOUTS	200809L

/* We support spinlocks.  */
#define _POSIX_SPIN_LOCKS	200809L

/* The `spawn' function family is supported.  */
#define _POSIX_SPAWN	200809L

/* We have POSIX timers.  */
#define _POSIX_TIMERS	200809L

/* The barrier functions are available.  */
#define _POSIX_BARRIERS	200809L

/* POSIX message queues are available.  */
#define	_POSIX_MESSAGE_PASSING	200809L

/* Thread process-shared synchronization is supported.  */
#define _POSIX_THREAD_PROCESS_SHARED	200809L

/* The monotonic clock might be available.  */
#define _POSIX_MONOTONIC_CLOCK	0

/* The clock selection interfaces are available.  */
#define _POSIX_CLOCK_SELECTION	200809L

/* Advisory information interfaces are available.  */
#define _POSIX_ADVISORY_INFO	200809L

/* IPv6 support is available.  */
#define _POSIX_IPV6	200809L

/* Raw socket support is available.  */
#define _POSIX_RAW_SOCKETS	200809L

/* We have at least one terminal.  */
#define _POSIX2_CHAR_TERM	200809L

/* Neither process nor thread sporadic server interfaces is available.  */
#define _POSIX_SPORADIC_SERVER	-1
#define _POSIX_THREAD_SPORADIC_SERVER	-1

/* trace.h is not available.  */
#define _POSIX_TRACE	-1
#define _POSIX_TRACE_EVENT_FILTER	-1
#define _POSIX_TRACE_INHERIT	-1
#define _POSIX_TRACE_LOG	-1

/* Typed memory objects are not available.  */
#define _POSIX_TYPED_MEMORY_OBJECTS	-1

/* Streams are not available.  */
#define _XOPEN_STREAMS	-1

#endif /* bits/posix_opt.h */

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