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7a80496f 1/* Copyright (C) 1991-1993,1995-2003, 2004 Free Software Foundation, Inc.
2c6fe0bd 2 This file is part of the GNU C Library.
28f540f4 3
2c6fe0bd 4 The GNU C Library is free software; you can redistribute it and/or
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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.
28f540f4 8
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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
41bdb6e2 12 Lesser General Public License for more details.
28f540f4 13
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14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
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18
19#ifndef _FEATURES_H
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20#define _FEATURES_H 1
21
22/* These are defined by the user (or the compiler)
23 to specify the desired environment:
24
d38cd08c 25 __STRICT_ANSI__ ISO Standard C.
ec751a23 26 _ISOC99_SOURCE Extensions to ISO C89 from ISO C99.
28f540f4 27 _POSIX_SOURCE IEEE Std 1003.1.
6d52618b 28 _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2;
118bad87 29 if >=199309L, add IEEE Std 1003.1b-1993;
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30 if >=199506L, add IEEE Std 1003.1c-1995;
31 if >=200112L, all of IEEE 1003.1-2004
a5a0310d 32 _XOPEN_SOURCE Includes POSIX and XPG things. Set to 500 if
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33 Single Unix conformance is wanted, to 600 for the
34 upcoming sixth revision.
2c6fe0bd 35 _XOPEN_SOURCE_EXTENDED XPG things and X/Open Unix extensions.
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36 _LARGEFILE_SOURCE Some more functions for correct standard I/O.
37 _LARGEFILE64_SOURCE Additional functionality from LFS for large files.
38 _FILE_OFFSET_BITS=N Select default filesystem interface.
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39 _BSD_SOURCE ISO C, POSIX, and 4.3BSD things.
40 _SVID_SOURCE ISO C, POSIX, and SVID things.
28f540f4 41 _GNU_SOURCE All of the above, plus GNU extensions.
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42 _REENTRANT Select additionally reentrant object.
43 _THREAD_SAFE Same as _REENTRANT, often used by other systems.
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44
45 The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__.
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46 If none of these are defined, the default is to have _SVID_SOURCE,
47 _BSD_SOURCE, and _POSIX_SOURCE set to one and _POSIX_C_SOURCE set to
48 199506L. If more than one of these are defined, they accumulate.
28f540f4 49 For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE
d38cd08c 50 together give you ISO C, 1003.1, and 1003.2, but nothing else.
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51
52 These are defined by this file and are used by the
53 header files to decide what to declare or define:
54
ec751a23 55 __USE_ISOC99 Define ISO C99 things.
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56 __USE_POSIX Define IEEE Std 1003.1 things.
57 __USE_POSIX2 Define IEEE Std 1003.2 things.
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58 __USE_POSIX199309 Define IEEE Std 1003.1, and .1b things.
59 __USE_POSIX199506 Define IEEE Std 1003.1, .1b, .1c and .1i things.
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60 __USE_XOPEN Define XPG things.
61 __USE_XOPEN_EXTENDED Define X/Open Unix things.
a5a0310d 62 __USE_UNIX98 Define Single Unix V2 things.
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63 __USE_XOPEN2K Define XPG6 things.
64 __USE_LARGEFILE Define correct standard I/O things.
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65 __USE_LARGEFILE64 Define LFS things with separate names.
66 __USE_FILE_OFFSET64 Define 64bit interface as default.
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67 __USE_BSD Define 4.3BSD things.
68 __USE_SVID Define SVID things.
69 __USE_MISC Define things common to BSD and System V Unix.
70 __USE_GNU Define GNU extensions.
aa910907 71 __USE_REENTRANT Define reentrant/thread-safe *_r functions.
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72 __FAVOR_BSD Favor 4.3BSD things in cases of conflict.
73
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74 The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are
75 defined by this file unconditionally. `__GNU_LIBRARY__' is provided
76 only for compatibility. All new code should use the other symbols
77 to test for features.
28f540f4 78
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79 All macros listed above as possibly being defined by this file are
80 explicitly undefined if they are not explicitly defined.
81 Feature-test macros that are not defined by the user or compiler
82 but are implied by the other feature-test macros defined (or by the
83 lack of any definitions) are defined by the file. */
84
85
86/* Undefine everything, so we get a clean slate. */
ec751a23 87#undef __USE_ISOC99
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88#undef __USE_POSIX
89#undef __USE_POSIX2
6d52618b 90#undef __USE_POSIX199309
4a582094 91#undef __USE_POSIX199506
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92#undef __USE_XOPEN
93#undef __USE_XOPEN_EXTENDED
dfd2257a 94#undef __USE_UNIX98
24d6fe58 95#undef __USE_XOPEN2K
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96#undef __USE_LARGEFILE
97#undef __USE_LARGEFILE64
98#undef __USE_FILE_OFFSET64
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99#undef __USE_BSD
100#undef __USE_SVID
101#undef __USE_MISC
102#undef __USE_GNU
aa910907 103#undef __USE_REENTRANT
28f540f4 104#undef __FAVOR_BSD
a1470b6f 105#undef __KERNEL_STRICT_NAMES
28f540f4 106
a1470b6f 107/* Suppress kernel-name space pollution unless user expressedly asks
2c6fe0bd 108 for it. */
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109#ifndef _LOOSE_KERNEL_NAMES
110# define __KERNEL_STRICT_NAMES
111#endif
28f540f4 112
d38cd08c 113/* Always use ISO C things. */
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114#define __USE_ANSI 1
115
116
117/* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */
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118#if defined _BSD_SOURCE && \
119 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \
df4ef2ab 120 defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \
d38cd08c 121 defined _GNU_SOURCE || defined _SVID_SOURCE)
2c6fe0bd 122# define __FAVOR_BSD 1
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123#endif
124
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125/* If _GNU_SOURCE was defined by the user, turn on all the other features. */
126#ifdef _GNU_SOURCE
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127# undef _ISOC99_SOURCE
128# define _ISOC99_SOURCE 1
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129# undef _POSIX_SOURCE
130# define _POSIX_SOURCE 1
131# undef _POSIX_C_SOURCE
dd7d45e8 132# define _POSIX_C_SOURCE 199506L
5107cf1d 133# undef _XOPEN_SOURCE
219aa9e9 134# define _XOPEN_SOURCE 600
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135# undef _XOPEN_SOURCE_EXTENDED
136# define _XOPEN_SOURCE_EXTENDED 1
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137# undef _LARGEFILE64_SOURCE
138# define _LARGEFILE64_SOURCE 1
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139# undef _BSD_SOURCE
140# define _BSD_SOURCE 1
141# undef _SVID_SOURCE
142# define _SVID_SOURCE 1
59dd8641 143#endif
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144
145/* If nothing (other than _GNU_SOURCE) is defined,
146 define _BSD_SOURCE and _SVID_SOURCE. */
ec751a23 147#if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \
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148 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \
149 !defined _XOPEN_SOURCE && !defined _XOPEN_SOURCE_EXTENDED && \
150 !defined _BSD_SOURCE && !defined _SVID_SOURCE)
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151# define _BSD_SOURCE 1
152# define _SVID_SOURCE 1
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153#endif
154
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155/* This is to enable the ISO C99 extension. Also recognize the old macro
156 which was used prior to the standard acceptance. This macro will
157 eventually go away and the features enabled by default once the ISO C99
158 standard is widely adopted. */
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159#if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \
160 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
ec751a23 161# define __USE_ISOC99 1
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162#endif
163
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164/* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2
165 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */
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166#if (!defined __STRICT_ANSI__ && !defined _POSIX_SOURCE && \
167 !defined _POSIX_C_SOURCE)
5107cf1d 168# define _POSIX_SOURCE 1
925e31d9 169# if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500
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170# define _POSIX_C_SOURCE 2
171# else
dd7d45e8 172# define _POSIX_C_SOURCE 199506L
5107cf1d 173# endif
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174#endif
175
d38cd08c 176#if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE
5107cf1d 177# define __USE_POSIX 1
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178#endif
179
d38cd08c 180#if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE
5107cf1d 181# define __USE_POSIX2 1
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182#endif
183
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184#if (_POSIX_C_SOURCE - 0) >= 199309L
185# define __USE_POSIX199309 1
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186#endif
187
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188#if (_POSIX_C_SOURCE - 0) >= 199506L
189# define __USE_POSIX199506 1
190#endif
191
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192#if (_POSIX_C_SOURCE - 0) >= 200112L
193# define __USE_XOPEN2K 1
194#endif
195
2c6fe0bd 196#ifdef _XOPEN_SOURCE
5107cf1d 197# define __USE_XOPEN 1
219aa9e9 198# if (_XOPEN_SOURCE - 0) >= 500
5107cf1d 199# define __USE_XOPEN_EXTENDED 1
a5a0310d 200# define __USE_UNIX98 1
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201# undef _LARGEFILE_SOURCE
202# define _LARGEFILE_SOURCE 1
925e31d9 203# if (_XOPEN_SOURCE - 0) >= 600
219aa9e9 204# define __USE_XOPEN2K 1
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205# undef __USE_ISOC99
206# define __USE_ISOC99 1
219aa9e9 207# endif
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208# else
209# ifdef _XOPEN_SOURCE_EXTENDED
210# define __USE_XOPEN_EXTENDED 1
211# endif
5107cf1d 212# endif
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213#endif
214
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215#ifdef _LARGEFILE_SOURCE
216# define __USE_LARGEFILE 1
217#endif
218
219#ifdef _LARGEFILE64_SOURCE
220# define __USE_LARGEFILE64 1
221#endif
222
223#if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64
224# define __USE_FILE_OFFSET64 1
225#endif
226
d38cd08c 227#if defined _BSD_SOURCE || defined _SVID_SOURCE
5107cf1d 228# define __USE_MISC 1
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229#endif
230
231#ifdef _BSD_SOURCE
5107cf1d 232# define __USE_BSD 1
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233#endif
234
235#ifdef _SVID_SOURCE
5107cf1d 236# define __USE_SVID 1
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237#endif
238
239#ifdef _GNU_SOURCE
5107cf1d 240# define __USE_GNU 1
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241#endif
242
d38cd08c 243#if defined _REENTRANT || defined _THREAD_SAFE
5107cf1d 244# define __USE_REENTRANT 1
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245#endif
246
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247/* We do support the IEC 559 math functionality, real and complex. */
248#define __STDC_IEC_559__ 1
249#define __STDC_IEC_559_COMPLEX__ 1
28f540f4 250
95589177 251/* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */
d3d99893 252#define __STDC_ISO_10646__ 200009L
91bc38d0 253
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254/* This macro indicates that the installed library is the GNU C Library.
255 For historic reasons the value now is 6 and this will stay from now
256 on. The use of this variable is deprecated. Use __GLIBC__ and
257 __GLIBC_MINOR__ now (see below) when you want to test for a specific
258 GNU C library version and use the values in <gnu/lib-names.h> to get
259 the sonames of the shared libraries. */
260#undef __GNU_LIBRARY__
261#define __GNU_LIBRARY__ 6
262
263/* Major and minor version number of the GNU C library package. Use
264 these macros to test for features in specific releases. */
265#define __GLIBC__ 2
269b4861 266#define __GLIBC_MINOR__ 3
28f540f4 267
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268/* Convenience macros to test the versions of glibc and gcc.
269 Use them like this:
270 #if __GNUC_PREREQ (2,8)
271 ... code requiring gcc 2.8 or later ...
272 #endif
273 Note - they won't work for gcc1 or glibc1, since the _MINOR macros
274 were not defined then. */
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275#if defined __GNUC__ && defined __GNUC_MINOR__
276# define __GNUC_PREREQ(maj, min) \
277 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
278#else
279# define __GNUC_PREREQ(maj, min) 0
280#endif
281
282#define __GLIBC_PREREQ(maj, min) \
283 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
4360eafd 284
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285/* Decide whether a compiler supports the long long datatypes. */
286#if defined __GNUC__ \
287 || (defined __PGI && defined __i386__ ) \
288 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \
12518320 289 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
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290# define __GLIBC_HAVE_LONG_LONG 1
291#endif
292
28f540f4 293/* This is here only because every header file already includes this one. */
edf5b2d7 294#ifndef __ASSEMBLER__
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295# ifndef _SYS_CDEFS_H
296# include <sys/cdefs.h>
297# endif
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298
299/* If we don't have __REDIRECT, prototypes will be missing if
300 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */
301# if defined __USE_FILE_OFFSET64 && !defined __REDIRECT
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302# define __USE_LARGEFILE 1
303# define __USE_LARGEFILE64 1
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304# endif
305
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306#endif /* !ASSEMBLER */
307
308/* Decide whether we can define 'extern inline' functions in headers. */
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309#if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \
310 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__
eedbbe58 311# define __USE_EXTERN_INLINES 1
edf5b2d7 312#endif
28f540f4 313
28f540f4 314
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315/* This is here only because every header file already includes this one.
316 Get the definitions of all the appropriate `__stub_FUNCTION' symbols.
317 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub
318 that will always return failure (and set errno to ENOSYS). */
319#include <gnu/stubs.h>
28f540f4 320
28f540f4 321
6ed0492f 322#endif /* features.h */