golden hour

/usr/include/bits

File/Folder	Size	Actions
a.out.h	268 B
byteswap-16.h	1.69 KB
byteswap.h	5.56 KB
cmathcalls.h	4.7 KB
confname.h	23.19 KB
dirent.h	1.69 KB
dlfcn.h	2.47 KB
elfclass.h	426 B
endian.h	176 B
environments.h	3.5 KB
epoll.h	1.11 KB
errno.h	2.11 KB
error.h	2.62 KB
eventfd.h	1.1 KB
fcntl-linux.h	12.55 KB
fcntl.h	2.19 KB
fcntl2.h	5.44 KB
fenv.h	3.94 KB
fenvinline.h	190 B
huge_val.h	1.83 KB
huge_valf.h	1.79 KB
huge_vall.h	1.57 KB
hwcap.h	966 B
in.h	9.01 KB
inf.h	1.03 KB
initspin.h	25 B
inotify.h	1.05 KB
ioctl-types.h	2.41 KB
ioctls.h	4.38 KB
ipc.h	2.01 KB
ipctypes.h	1.14 KB
libc-lock.h	12.54 KB
libio-ldbl.h	1014 B
link.h	4.2 KB
local_lim.h	3.13 KB
locale.h	1.33 KB
math-finite.h	14.24 KB
mathcalls.h	11.3 KB
mathdef.h	2.14 KB
mathinline.h	30.86 KB
mman.h	4.78 KB
monetary-ldbl.h	1.02 KB
mqueue.h	1.22 KB
mqueue2.h	2.11 KB
msq.h	2.47 KB
nan.h	1.54 KB
netdb.h	1.25 KB
param.h	1.4 KB
poll.h	2.04 KB
poll2.h	2.86 KB
posix1_lim.h	4.81 KB
posix2_lim.h	2.82 KB
posix_opt.h	5.65 KB
printf-ldbl.h	986 B
pthreadtypes.h	6.33 KB
resource.h	9.21 KB
sched.h	7.37 KB
select.h	2.08 KB
select2.h	1.4 KB
sem.h	2.53 KB
semaphore.h	1.21 KB
setjmp.h	1.26 KB
setjmp2.h	1.67 KB
shm.h	3.44 KB
sigaction.h	2.79 KB
sigcontext.h	4.08 KB
siginfo.h	9.81 KB
signalfd.h	1.04 KB
signum.h	3.34 KB
sigset.h	4.48 KB
sigstack.h	1.49 KB
sigthread.h	1.64 KB
sockaddr.h	1.5 KB
socket.h	12.6 KB
socket2.h	2.95 KB
socket_type.h	2.16 KB
stab.def	8.82 KB
stat.h	7.46 KB
statfs.h	1.89 KB
statvfs.h	3.34 KB
stdio-ldbl.h	3.11 KB
stdio-lock.h	2.14 KB
stdio.h	5.45 KB
stdio2.h	12.36 KB
stdio_lim.h	1.34 KB
stdlib-float.h	1.12 KB
stdlib-ldbl.h	1.36 KB
stdlib.h	5.53 KB
string.h	56.48 KB
string2.h	46.08 KB
string3.h	4.38 KB
sys_errlist.h	1.19 KB
syscall.h	43.03 KB
sysctl.h	893 B
syslog-ldbl.h	1.17 KB
syslog-path.h	1.03 KB
syslog.h	1.66 KB
termios.h	5.23 KB
time.h	3.35 KB
timerfd.h	1.08 KB
timex.h	4.36 KB
types.h	7.55 KB
typesizes.h	3.15 KB
uio.h	2.42 KB
unistd.h	13.07 KB
ustat.h	1.06 KB
utmp.h	3.87 KB
utmpx.h	3.38 KB
utsname.h	1.19 KB
waitflags.h	1.61 KB
waitstatus.h	3.49 KB
wchar-ldbl.h	2.45 KB
wchar.h	1.11 KB
wchar2.h	20.04 KB
wordsize.h	327 B
xopen_lim.h	3.68 KB

Edit: sigset.h

/* __sig_atomic_t, __sigset_t, and related definitions.  Linux version.
   Copyright (C) 1991, 1992, 1994, 1996, 1997, 2007, 2012
   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/>.  */

#ifndef	_SIGSET_H_types
# define _SIGSET_H_types	1

typedef int __sig_atomic_t;

/* A `sigset_t' has a bit for each signal.  */

# define _SIGSET_NWORDS	(1024 / (8 * sizeof (unsigned long int)))
typedef struct
  {
    unsigned long int __val[_SIGSET_NWORDS];
  } __sigset_t;

#endif

/* We only want to define these functions if <signal.h> was actually
   included; otherwise we were included just to define the types.  Since we
   are namespace-clean, it wouldn't hurt to define extra macros.  But
   trouble can be caused by functions being defined (e.g., any global
   register vars declared later will cause compilation errors).  */

#if !defined _SIGSET_H_fns && defined _SIGNAL_H
# define _SIGSET_H_fns 1

# ifndef _EXTERN_INLINE
#  define _EXTERN_INLINE __extern_inline
# endif

/* Return a mask that includes the bit for SIG only.  */
# define __sigmask(sig) \
  (((unsigned long int) 1) << (((sig) - 1) % (8 * sizeof (unsigned long int))))

/* Return the word index for SIG.  */
# define __sigword(sig)	(((sig) - 1) / (8 * sizeof (unsigned long int)))

# if defined __GNUC__ && __GNUC__ >= 2
#  define __sigemptyset(set) \
  (__extension__ ({ int __cnt = _SIGSET_NWORDS;				      \
		    sigset_t *__set = (set);				      \
		    while (--__cnt >= 0) __set->__val[__cnt] = 0;	      \
		    0; }))
#  define __sigfillset(set) \
  (__extension__ ({ int __cnt = _SIGSET_NWORDS;				      \
		    sigset_t *__set = (set);				      \
		    while (--__cnt >= 0) __set->__val[__cnt] = ~0UL;	      \
		    0; }))

#  ifdef __USE_GNU
/* The POSIX does not specify for handling the whole signal set in one
   command.  This is often wanted and so we define three more functions
   here.  */
#   define __sigisemptyset(set) \
  (__extension__ ({ int __cnt = _SIGSET_NWORDS;				      \
		    const sigset_t *__set = (set);			      \
		    int __ret = __set->__val[--__cnt];			      \
		    while (!__ret && --__cnt >= 0)			      \
			__ret = __set->__val[__cnt];			      \
		    __ret == 0; }))
#   define __sigandset(dest, left, right) \
  (__extension__ ({ int __cnt = _SIGSET_NWORDS;				      \
		    sigset_t *__dest = (dest);				      \
		    const sigset_t *__left = (left);			      \
		    const sigset_t *__right = (right);			      \
		    while (--__cnt >= 0)				      \
		      __dest->__val[__cnt] = (__left->__val[__cnt]	      \
					      & __right->__val[__cnt]);	      \
		    0; }))
#   define __sigorset(dest, left, right) \
  (__extension__ ({ int __cnt = _SIGSET_NWORDS;				      \
		    sigset_t *__dest = (dest);				      \
		    const sigset_t *__left = (left);			      \
		    const sigset_t *__right = (right);			      \
		    while (--__cnt >= 0)				      \
		      __dest->__val[__cnt] = (__left->__val[__cnt]	      \
					      | __right->__val[__cnt]);	      \
		    0; }))
#  endif
# endif

/* These functions needn't check for a bogus signal number -- error
   checking is done in the non __ versions.  */

extern int __sigismember (const __sigset_t *, int);
extern int __sigaddset (__sigset_t *, int);
extern int __sigdelset (__sigset_t *, int);

# ifdef __USE_EXTERN_INLINES
#  define __SIGSETFN(NAME, BODY, CONST)					      \
  _EXTERN_INLINE int							      \
  NAME (CONST __sigset_t *__set, int __sig)				      \
  {									      \
    unsigned long int __mask = __sigmask (__sig);			      \
    unsigned long int __word = __sigword (__sig);			      \
    return BODY;							      \
  }

__SIGSETFN (__sigismember, (__set->__val[__word] & __mask) ? 1 : 0, const)
__SIGSETFN (__sigaddset, ((__set->__val[__word] |= __mask), 0), )
__SIGSETFN (__sigdelset, ((__set->__val[__word] &= ~__mask), 0), )

#  undef __SIGSETFN
# endif

#endif /* ! _SIGSET_H_fns.  */