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The C and C++ Include Header Files
cat -n /usr/include/c++/15/cstdlib
1 // -*- C++ -*- forwarding header. 2 3 // Copyright (C) 1997-2025 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file include/cstdlib 26 * This is a Standard C++ Library file. You should @c \#include this file 27 * in your programs, rather than any of the @a *.h implementation files. 28 * 29 * This is the C++ version of the Standard C Library header @c stdlib.h, 30 * and its contents are (mostly) the same as that header, but are all 31 * contained in the namespace @c std (except for names which are defined 32 * as macros in C). 33 */ 34 35 // 36 // ISO C++ 14882: 20.4.6 C library 37 // 38 39 #ifndef _GLIBCXX_CSTDLIB 40 #define _GLIBCXX_CSTDLIB 1 41 42 #ifdef _GLIBCXX_SYSHDR 43 #pragma GCC system_header 44 #endif 45 46 #include <bits/c++config.h> 47 48 #if !_GLIBCXX_HOSTED 49 // The C standard does not require a freestanding implementation to 50 // provide <stdlib.h>. However, the C++ standard does still require 51 // <cstdlib> -- but only the functionality mentioned in 52 // [lib.support.start.term]. 53 54 #define EXIT_SUCCESS 0 55 #define EXIT_FAILURE 1 56 #define NULL __null 57 58 namespace std 59 { 60 extern "C" void abort(void) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN; 61 extern "C" int atexit(void (*)(void)) _GLIBCXX_NOTHROW; 62 extern "C" void exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN; 63 #if __cplusplus >= 201103L 64 # ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT 65 extern "C" int at_quick_exit(void (*)(void)) _GLIBCXX_NOTHROW; 66 # endif 67 # ifdef _GLIBCXX_HAVE_QUICK_EXIT 68 extern "C" void quick_exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN; 69 # endif 70 #if _GLIBCXX_USE_C99_STDLIB 71 extern "C" void _Exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN; 72 #endif 73 #endif 74 } // namespace std 75 76 #else 77 78 // Need to ensure this finds the C library's <stdlib.h> not a libstdc++ 79 // wrapper that might already be installed later in the include search path. 80 #pragma GCC diagnostic push 81 #pragma GCC diagnostic ignored "-Wpedantic" // include_next 82 #define _GLIBCXX_INCLUDE_NEXT_C_HEADERS 83 #include_next <stdlib.h> 84 #undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS 85 #pragma GCC diagnostic pop 86 87 #include <bits/std_abs.h> 88 89 // Get rid of those macros defined in <stdlib.h> in lieu of real functions. 90 #undef abort 91 #if __cplusplus >= 201703L && defined(_GLIBCXX_HAVE_ALIGNED_ALLOC) 92 # undef aligned_alloc 93 #endif 94 #undef atexit 95 #if __cplusplus >= 201103L 96 # ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT 97 # undef at_quick_exit 98 # endif 99 #endif 100 #undef atof 101 #undef atoi 102 #undef atol 103 #undef bsearch 104 #undef calloc 105 #undef div 106 #undef exit 107 #undef free 108 #undef getenv 109 #undef labs 110 #undef ldiv 111 #undef malloc 112 #undef mblen 113 #undef mbstowcs 114 #undef mbtowc 115 #undef qsort 116 #if __cplusplus >= 201103L 117 # ifdef _GLIBCXX_HAVE_QUICK_EXIT 118 # undef quick_exit 119 # endif 120 #endif 121 #undef rand 122 #undef realloc 123 #undef srand 124 #undef strtod 125 #undef strtol 126 #undef strtoul 127 #undef system 128 #undef wcstombs 129 #undef wctomb 130 131 extern "C++" 132 { 133 namespace std _GLIBCXX_VISIBILITY(default) 134 { 135 _GLIBCXX_BEGIN_NAMESPACE_VERSION 136 137 using ::div_t; 138 using ::ldiv_t; 139 140 using ::abort; 141 #if __cplusplus >= 201703L && defined(_GLIBCXX_HAVE_ALIGNED_ALLOC) 142 using ::aligned_alloc; 143 #endif 144 using ::atexit; 145 #if __cplusplus >= 201103L 146 # ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT 147 using ::at_quick_exit; 148 # endif 149 #endif 150 using ::atof; 151 using ::atoi; 152 using ::atol; 153 using ::bsearch; 154 using ::calloc; 155 using ::div; 156 using ::exit; 157 using ::free; 158 using ::getenv; 159 using ::labs; 160 using ::ldiv; 161 using ::malloc; 162 #ifdef _GLIBCXX_HAVE_MBSTATE_T 163 using ::mblen; 164 using ::mbstowcs; 165 using ::mbtowc; 166 #endif // _GLIBCXX_HAVE_MBSTATE_T 167 using ::qsort; 168 #if __cplusplus >= 201103L 169 # ifdef _GLIBCXX_HAVE_QUICK_EXIT 170 using ::quick_exit; 171 # endif 172 #endif 173 using ::rand; 174 using ::realloc; 175 using ::srand; 176 using ::strtod; 177 using ::strtol; 178 using ::strtoul; 179 using ::system; 180 #ifdef _GLIBCXX_USE_WCHAR_T 181 using ::wcstombs; 182 using ::wctomb; 183 #endif // _GLIBCXX_USE_WCHAR_T 184 185 #ifndef __CORRECT_ISO_CPP_STDLIB_H_PROTO 186 inline ldiv_t 187 div(long __i, long __j) _GLIBCXX_NOTHROW { return ldiv(__i, __j); } 188 #endif 189 190 191 _GLIBCXX_END_NAMESPACE_VERSION 192 } // namespace 193 194 #if _GLIBCXX_USE_C99_STDLIB 195 196 #undef _Exit 197 #undef llabs 198 #undef lldiv 199 #undef atoll 200 #undef strtoll 201 #undef strtoull 202 #undef strtof 203 #undef strtold 204 205 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 206 { 207 _GLIBCXX_BEGIN_NAMESPACE_VERSION 208 209 #if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC 210 using ::lldiv_t; 211 #endif 212 #if _GLIBCXX_USE_C99_CHECK || _GLIBCXX_USE_C99_DYNAMIC 213 extern "C" void (_Exit)(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN; 214 #endif 215 #if !_GLIBCXX_USE_C99_DYNAMIC 216 using ::_Exit; 217 #endif 218 219 #if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC 220 #pragma GCC diagnostic push 221 #pragma GCC diagnostic ignored "-Wlong-long" 222 using ::llabs; 223 224 inline lldiv_t 225 div(long long __n, long long __d) 226 { lldiv_t __q; __q.quot = __n / __d; __q.rem = __n % __d; return __q; } 227 228 using ::lldiv; 229 #pragma GCC diagnostic pop 230 #endif 231 232 #if _GLIBCXX_USE_C99_LONG_LONG_CHECK || _GLIBCXX_USE_C99_LONG_LONG_DYNAMIC 233 extern "C" long long int (atoll)(const char *) _GLIBCXX_NOTHROW; 234 extern "C" long long int 235 (strtoll)(const char * __restrict, char ** __restrict, int) _GLIBCXX_NOTHROW; 236 extern "C" unsigned long long int 237 (strtoull)(const char * __restrict, char ** __restrict, int) _GLIBCXX_NOTHROW; 238 #endif 239 #if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC 240 using ::atoll; 241 using ::strtoll; 242 using ::strtoull; 243 #endif 244 using ::strtof; 245 using ::strtold; 246 247 _GLIBCXX_END_NAMESPACE_VERSION 248 } // namespace __gnu_cxx 249 250 namespace std 251 { 252 #if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC 253 using ::__gnu_cxx::lldiv_t; 254 #endif 255 using ::__gnu_cxx::_Exit; 256 #if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC 257 using ::__gnu_cxx::llabs; 258 using ::__gnu_cxx::div; 259 using ::__gnu_cxx::lldiv; 260 #endif 261 using ::__gnu_cxx::atoll; 262 using ::__gnu_cxx::strtof; 263 using ::__gnu_cxx::strtoll; 264 using ::__gnu_cxx::strtoull; 265 using ::__gnu_cxx::strtold; 266 } // namespace std 267 268 #else // ! _GLIBCXX_USE_C99_STDLIB 269 270 // We also check for strtof and strtold separately from _GLIBCXX_USE_C99_STDLIB 271 272 #if _GLIBCXX_HAVE_STRTOF 273 #undef strtof 274 namespace std { using ::strtof; } 275 #endif 276 277 #if _GLIBCXX_HAVE_STRTOLD 278 #undef strtold 279 namespace std { using ::strtold; } 280 #endif 281 282 #endif // _GLIBCXX_USE_C99_STDLIB 283 284 } // extern "C++" 285 286 #endif // !_GLIBCXX_HOSTED 287 288 #endif
