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+/* Copyright (C) 1991, 92, 93, 95, 96, 97 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 Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#ifndef _FEATURES_H
+#define _FEATURES_H 1
+
+/* These are defined by the user (or the compiler)
+ to specify the desired environment:
+
+ __STRICT_ANSI__ ISO Standard C.
+ _ISOC9X_SOURCE Extensions to ISO C 89 from ISO C 9x.
+ _POSIX_SOURCE IEEE Std 1003.1.
+ _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2;
+ if >=199309L, add IEEE Std 1003.1b-1993
+ _XOPEN_SOURCE Includes POSIX and XPG things.
+ _XOPEN_SOURCE_EXTENDED XPG things and X/Open Unix extensions.
+ _BSD_SOURCE ISO C, POSIX, and 4.3BSD things.
+ _SVID_SOURCE ISO C, POSIX, and SVID things.
+ _GNU_SOURCE All of the above, plus GNU extensions.
+ _REENTRANT Select additionally reentrant object.
+ _THREAD_SAFE Same as _REENTRANT, often used by other systems.
+
+ The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__.
+ If none of these are defined, the default is all but _GNU_SOURCE.
+ If more than one of these are defined, they accumulate.
+ For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE
+ together give you ISO C, 1003.1, and 1003.2, but nothing else.
+
+ These are defined by this file and are used by the
+ header files to decide what to declare or define:
+
+ __USE_ISOC9X Define ISO C 9X things.
+ __USE_POSIX Define IEEE Std 1003.1 things.
+ __USE_POSIX2 Define IEEE Std 1003.2 things.
+ __USE_POSIX199309 Define IEEE Std 1003.1b things.
+ __USE_XOPEN Define XPG things.
+ __USE_XOPEN_EXTENDED Define X/Open Unix things.
+ __USE_BSD Define 4.3BSD things.
+ __USE_SVID Define SVID things.
+ __USE_MISC Define things common to BSD and System V Unix.
+ __USE_GNU Define GNU extensions.
+ __USE_REENTRANT Define reentrant/thread-safe *_r functions.
+ __FAVOR_BSD Favor 4.3BSD things in cases of conflict.
+
+ The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are
+ defined by this file unconditionally. `__GNU_LIBRARY__' is provided
+ only for compatibility. All new code should use the other symbols
+ to test for features.
+
+ All macros listed above as possibly being defined by this file are
+ explicitly undefined if they are not explicitly defined.
+ Feature-test macros that are not defined by the user or compiler
+ but are implied by the other feature-test macros defined (or by the
+ lack of any definitions) are defined by the file. */
+
+
+/* Undefine everything, so we get a clean slate. */
+#undef __USE_ISOC9X
+#undef __USE_POSIX
+#undef __USE_POSIX2
+#undef __USE_POSIX199309
+#undef __USE_XOPEN
+#undef __USE_XOPEN_EXTENDED
+#undef __USE_BSD
+#undef __USE_SVID
+#undef __USE_MISC
+#undef __USE_GNU
+#undef __USE_REENTRANT
+#undef __FAVOR_BSD
+#undef __KERNEL_STRICT_NAMES
+
+/* Suppress kernel-name space pollution unless user expressedly asks
+ for it. */
+#ifndef _LOOSE_KERNEL_NAMES
+# define __KERNEL_STRICT_NAMES
+#endif
+
+/* Always use ISO C things. */
+#define __USE_ANSI 1
+
+
+/* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */
+#if defined _BSD_SOURCE && \
+ !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \
+ defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \
+ defined _GNU_SOURCE || defined _SVID_SOURCE)
+# define __FAVOR_BSD 1
+#endif
+
+/* If _GNU_SOURCE was defined by the user, turn on all the other features. */
+#ifdef _GNU_SOURCE
+# undef _ISOC9X_SOURCE
+# define _ISOC9X_SOURCE 1
+# undef _POSIX_SOURCE
+# define _POSIX_SOURCE 1
+# undef _POSIX_C_SOURCE
+# define _POSIX_C_SOURCE 199309L
+# undef _XOPEN_SOURCE
+# define _XOPEN_SOURCE 1
+# undef _XOPEN_SOURCE_EXTENDED
+# define _XOPEN_SOURCE_EXTENDED 1
+# undef _BSD_SOURCE
+# define _BSD_SOURCE 1
+# undef _SVID_SOURCE
+# define _SVID_SOURCE 1
+#endif
+
+/* If nothing (other than _GNU_SOURCE) is defined,
+ define _BSD_SOURCE and _SVID_SOURCE. */
+#if (!defined __STRICT_ANSI__ && !defined _ISOC9X_SOURCE && \
+ !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \
+ !defined _XOPEN_SOURCE && !defined _XOPEN_SOURCE_EXTENDED && \
+ !defined _BSD_SOURCE && !defined _SVID_SOURCE)
+# define _BSD_SOURCE 1
+# define _SVID_SOURCE 1
+#endif
+
+/* This is to enable the ISO C 9x extension. It will go away as soon
+ as this standard is officially released. */
+#ifdef _ISOC9X_SOURCE
+# define __USE_ISOC9X 1
+#endif
+
+/* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2
+ (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */
+#if (!defined __STRICT_ANSI__ && !defined _POSIX_SOURCE && \
+ !defined _POSIX_C_SOURCE)
+# define _POSIX_SOURCE 1
+# ifdef _XOPEN_SOURCE
+# define _POSIX_C_SOURCE 2
+# else
+# define _POSIX_C_SOURCE 199309L
+# endif
+#endif
+
+#if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE
+# define __USE_POSIX 1
+#endif
+
+#if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE
+# define __USE_POSIX2 1
+#endif
+
+#if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 199309L
+# define __USE_POSIX199309 1
+#endif
+
+#ifdef _XOPEN_SOURCE
+# define __USE_XOPEN 1
+# ifdef _XOPEN_SOURCE_EXTENDED
+# define __USE_XOPEN_EXTENDED 1
+# endif
+#endif
+
+#if defined _BSD_SOURCE || defined _SVID_SOURCE
+# define __USE_MISC 1
+#endif
+
+#ifdef _BSD_SOURCE
+# define __USE_BSD 1
+#endif
+
+#ifdef _SVID_SOURCE
+# define __USE_SVID 1
+#endif
+
+#ifdef _GNU_SOURCE
+# define __USE_GNU 1
+#endif
+
+#if defined _REENTRANT || defined _THREAD_SAFE
+# define __USE_REENTRANT 1
+#endif
+
+/* We do support the IEC 559 math functionality, real and complex. */
+#define __STDC_IEC_559__ 1
+#define __STDC_IEC_559_COMPLEX__ 1
+
+/* This macro indicates that the installed library is the GNU C Library.
+ For historic reasons the value now is 6 and this will stay from now
+ on. The use of this variable is deprecated. Use __GLIBC__ and
+ __GLIBC_MINOR__ now (see below) when you want to test for a specific
+ GNU C library version and use the values in <gnu/lib-names.h> to get
+ the sonames of the shared libraries. */
+#undef __GNU_LIBRARY__
+#define __GNU_LIBRARY__ 6
+
+/* Major and minor version number of the GNU C library package. Use
+ these macros to test for features in specific releases. */
+#define __GLIBC__ 2
+#define __GLIBC_MINOR__ 1
+
+
+#if !defined __GNUC__ || __GNUC__ < 2
+/* In GCC version 2, (__extension__ EXPR) will not complain
+ about GCC extensions used in EXPR under -ansi or -pedantic. */
+# define __extension__
+#endif
+
+
+/* This is here only because every header file already includes this one. */
+#ifndef __ASSEMBLER__
+# include <sys/cdefs.h>
+#endif
+
+/* This is here only because every header file already includes this one. */
+#ifndef _LIBC
+/* Get the definitions of all the appropriate `__stub_FUNCTION' symbols.
+ <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub
+ which will always return failure (and set errno to ENOSYS).
+
+ We avoid including <gnu/stubs.h> when compiling the C library itself to
+ avoid a dependency loop. stubs.h depends on every object file. If
+ this #include were done for the library source code, then every object
+ file would depend on stubs.h. */
+
+# include <gnu/stubs.h>
+#endif
+
+#endif /* features.h */