Difference between revisions of "cpp/header/cstdlib"
From cppreference.com
(Added LWG issue #286 DR.) |
(Applied P2338R4 (Freestanding Library: Character primitives and the C library).) |
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{{dsc begin}} | {{dsc begin}} | ||
− | {{dsc h1 | Types}} | + | {{dsc h1|Types}} |
− | {{dsc inc | cpp/numeric/math/dsc div_t}} | + | {{dsc inc|cpp/numeric/math/dsc div_t}} |
− | {{dsc inc | cpp/numeric/math/dsc ldiv_t}} | + | {{dsc inc|cpp/numeric/math/dsc ldiv_t}} |
− | {{dsc inc | cpp/numeric/math/dsc lldiv_t}} | + | {{dsc inc|cpp/numeric/math/dsc lldiv_t}} |
− | {{dsc inc | cpp/types/dsc size_t}} | + | {{dsc inc|cpp/types/dsc size_t}} |
− | {{dsc h1 | Macro constants}} | + | {{dsc h1|Macro constants}} |
− | {{dsc inc | cpp/utility/program/dsc EXIT_status}} | + | {{dsc inc|cpp/utility/program/dsc EXIT_status}} |
− | {{dsc inc | cpp/numeric/random/dsc MB_CUR_MAX}} | + | {{dsc inc|cpp/numeric/random/dsc MB_CUR_MAX}} |
− | {{dsc inc | cpp/types/dsc NULL}} | + | {{dsc inc|cpp/types/dsc NULL}} |
− | {{dsc inc | cpp/numeric/random/dsc RAND_MAX}} | + | {{dsc inc|cpp/numeric/random/dsc RAND_MAX}} |
− | {{dsc h1 | Functions}} | + | {{dsc h1|Functions}} |
− | {{dsc h2 | Process control}} | + | {{dsc h2|Process control}} |
− | {{dsc inc | cpp/utility/program/dsc abort}} | + | {{dsc inc|cpp/utility/program/dsc abort}} |
− | {{dsc inc | cpp/utility/program/dsc exit}} | + | {{dsc inc|cpp/utility/program/dsc exit}} |
− | {{dsc inc | cpp/utility/program/dsc quick_exit}} | + | {{dsc inc|cpp/utility/program/dsc quick_exit}} |
− | {{dsc inc | cpp/utility/program/dsc _Exit}} | + | {{dsc inc|cpp/utility/program/dsc _Exit}} |
− | {{dsc inc | cpp/utility/program/dsc atexit}} | + | {{dsc inc|cpp/utility/program/dsc atexit}} |
− | {{dsc inc | cpp/utility/program/dsc at_quick_exit}} | + | {{dsc inc|cpp/utility/program/dsc at_quick_exit}} |
− | {{dsc inc | cpp/utility/program/dsc system}} | + | {{dsc inc|cpp/utility/program/dsc system}} |
− | {{dsc inc | cpp/utility/program/dsc getenv}} | + | {{dsc inc|cpp/utility/program/dsc getenv}} |
− | {{dsc h2 | Memory management}} | + | {{dsc h2|Memory management}} |
− | {{dsc inc | cpp/memory/c/dsc malloc}} | + | {{dsc inc|cpp/memory/c/dsc malloc}} |
− | {{dsc inc | cpp/memory/c/dsc aligned_alloc}} | + | {{dsc inc|cpp/memory/c/dsc aligned_alloc}} |
− | {{dsc inc | cpp/memory/c/dsc calloc}} | + | {{dsc inc|cpp/memory/c/dsc calloc}} |
− | {{dsc inc | cpp/memory/c/dsc realloc}} | + | {{dsc inc|cpp/memory/c/dsc realloc}} |
− | {{dsc inc | cpp/memory/c/dsc free}} | + | {{dsc inc|cpp/memory/c/dsc free}} |
− | {{dsc h2 | Numeric string conversion}} | + | {{dsc h2|Numeric string conversion}} |
− | {{dsc inc | cpp/string/byte/dsc atof}} | + | {{dsc inc|cpp/string/byte/dsc atof}} |
− | {{dsc inc | cpp/string/byte/dsc atoi}} | + | {{dsc inc|cpp/string/byte/dsc atoi}} |
− | {{dsc inc | cpp/string/byte/dsc strtol}} | + | {{dsc inc|cpp/string/byte/dsc strtol}} |
− | {{dsc inc | cpp/string/byte/dsc strtoul}} | + | {{dsc inc|cpp/string/byte/dsc strtoul}} |
− | {{dsc inc | cpp/string/byte/dsc strtof}} | + | {{dsc inc|cpp/string/byte/dsc strtof}} |
− | {{dsc h2 | Wide string manipulation}} | + | {{dsc h2|Wide string manipulation}} |
− | {{dsc inc | cpp/string/multibyte/dsc mblen}} | + | {{dsc inc|cpp/string/multibyte/dsc mblen}} |
− | {{dsc inc | cpp/string/multibyte/dsc mbtowc}} | + | {{dsc inc|cpp/string/multibyte/dsc mbtowc}} |
− | {{dsc inc | cpp/string/multibyte/dsc wctomb}} | + | {{dsc inc|cpp/string/multibyte/dsc wctomb}} |
− | {{dsc inc | cpp/string/multibyte/dsc mbstowcs}} | + | {{dsc inc|cpp/string/multibyte/dsc mbstowcs}} |
− | {{dsc inc | cpp/string/multibyte/dsc wcstombs}} | + | {{dsc inc|cpp/string/multibyte/dsc wcstombs}} |
− | {{dsc h2 | Miscellaneous algorithms and math}} | + | {{dsc h2|Miscellaneous algorithms and math}} |
− | {{dsc inc | cpp/numeric/random/dsc rand}} | + | {{dsc inc|cpp/numeric/random/dsc rand}} |
− | {{dsc inc | cpp/numeric/random/dsc srand}} | + | {{dsc inc|cpp/numeric/random/dsc srand}} |
− | {{dsc inc | cpp/algorithm/dsc qsort}} | + | {{dsc inc|cpp/algorithm/dsc qsort}} |
− | {{dsc inc | cpp/algorithm/dsc bsearch}} | + | {{dsc inc|cpp/algorithm/dsc bsearch}} |
− | {{dsc inc | cpp/numeric/math/dsc abs}} | + | {{dsc inc|cpp/numeric/math/dsc abs}} |
− | {{dsc inc | cpp/numeric/math/dsc div}} | + | {{dsc inc|cpp/numeric/math/dsc div}} |
{{dsc end}} | {{dsc end}} | ||
Line 61: | Line 61: | ||
{{source|1= | {{source|1= | ||
namespace std { | namespace std { | ||
− | using size_t = /* see description */; | + | using size_t = /* see description */; // freestanding |
− | using div_t = /* see description */; | + | using div_t = /* see description */; // freestanding |
− | using ldiv_t = /* see description */; | + | using ldiv_t = /* see description */; // freestanding |
− | using lldiv_t = /* see description */; | + | using lldiv_t = /* see description */; // freestanding |
} | } | ||
− | #define NULL /* see description */ | + | #define NULL /* see description */ // freestanding |
− | #define EXIT_FAILURE /* see description */ | + | #define EXIT_FAILURE /* see description */ // freestanding |
− | #define EXIT_SUCCESS /* see description */ | + | #define EXIT_SUCCESS /* see description */ // freestanding |
#define RAND_MAX /* see description */ | #define RAND_MAX /* see description */ | ||
#define MB_CUR_MAX /* see description */ | #define MB_CUR_MAX /* see description */ | ||
Line 75: | Line 75: | ||
namespace std { | namespace std { | ||
// Exposition-only function type aliases | // Exposition-only function type aliases | ||
− | extern "C" using /*c-atexit-handler*/ = void(); | + | extern "C" using /* c-atexit-handler */ = void(); // exposition only |
− | extern "C++" using /*atexit-handler*/ = void(); | + | extern "C++" using /* atexit-handler */ = void(); // exposition only |
− | extern "C" using /*c-compare-pred*/ = int(const void*, const void*); | + | extern "C" using /* c-compare-pred */ = // exposition only |
− | extern "C++" using /*compare-pred*/ = int(const void*, const void*); | + | int(const void*, const void*); |
+ | extern "C++" using /* compare-pred */ = // exposition only | ||
+ | int(const void*, const void*); | ||
// start and termination | // start and termination | ||
− | [[noreturn]] void abort() noexcept; | + | [[noreturn]] void abort() noexcept; // freestanding |
− | int atexit(/*c-atexit-handler*/* func) noexcept; | + | int atexit(/* c-atexit-handler */* func) noexcept; // freestanding |
− | int atexit(/*atexit-handler*/* func) noexcept; | + | int atexit(/* atexit-handler */* func) noexcept; // freestanding |
− | int at_quick_exit(/*c-atexit-handler*/* func) noexcept; | + | int at_quick_exit(/* c-atexit-handler */* func) noexcept; // freestanding |
− | int at_quick_exit(/*atexit-handler*/* func) noexcept; | + | int at_quick_exit(/* atexit-handler */* func) noexcept; // freestanding |
− | [[noreturn]] void exit(int status); | + | [[noreturn]] void exit(int status); // freestanding |
− | [[noreturn]] void _Exit(int status) noexcept; | + | [[noreturn]] void _Exit(int status) noexcept; // freestanding |
− | [[noreturn]] void quick_exit(int status) noexcept; | + | [[noreturn]] void quick_exit(int status) noexcept; // freestanding |
char* getenv(const char* name); | char* getenv(const char* name); | ||
Line 120: | Line 122: | ||
// C standard library algorithms | // C standard library algorithms | ||
− | void* bsearch(const void* key, const void* base, size_t nmemb, size_t size, | + | void* bsearch(const void* key, const void* base, // freestanding |
− | + | size_t nmemb, size_t size, /* c-compare-pred */* compar); | |
− | void* bsearch(const void* key, const void* base, size_t nmemb, size_t size, | + | void* bsearch(const void* key, const void* base, // freestanding |
− | + | size_t nmemb, size_t size, /* compare-pred */* compar); | |
− | void qsort(void* base, size_t nmemb, size_t size, /*c-compare-pred*/* compar); | + | void qsort(void* base, size_t nmemb, size_t size, // freestanding |
− | void qsort(void* base, size_t nmemb, size_t size, /*compare-pred*/* compar); | + | /* c-compare-pred */* compar); |
+ | void qsort(void* base, size_t nmemb, size_t size, // freestanding | ||
+ | /* compare-pred */* compar); | ||
// low-quality random number generation | // low-quality random number generation | ||
Line 132: | Line 136: | ||
// absolute values | // absolute values | ||
− | constexpr int abs(int j); | + | constexpr int abs(int j); // freestanding |
− | constexpr long int abs(long int j); | + | constexpr long int abs(long int j); // freestanding |
− | constexpr long long int abs(long long int j); | + | constexpr long long int abs(long long int j); // freestanding |
− | + | constexpr /* floating-point-type */ | |
− | constexpr | + | abs(/* floating-point-type */ j); // freestanding-deleted |
− | + | ||
− | constexpr long int labs(long int j); | + | constexpr long int labs(long int j); // freestanding |
− | constexpr long long int llabs(long long int j); | + | constexpr long long int llabs(long long int j); // freestanding |
− | constexpr div_t div(int numer, int denom); | + | constexpr div_t div(int numer, int denom); // freestanding |
− | constexpr ldiv_t div(long int numer, long int denom); | + | constexpr ldiv_t div(long int numer, long int denom); // freestanding |
− | constexpr lldiv_t div(long long int numer, long long int denom); | + | constexpr lldiv_t div(long long int numer, long long int denom); // freestanding |
− | constexpr ldiv_t ldiv(long int numer, long int denom); | + | constexpr ldiv_t ldiv(long int numer, long int denom); // freestanding |
− | constexpr lldiv_t lldiv(long long int numer, long long int denom); | + | constexpr lldiv_t lldiv(long long int numer, long long int denom); // freestanding |
} | } | ||
}} | }} |
Latest revision as of 23:53, 12 September 2023
This header was originally in the C standard library as <stdlib.h>.
This header provides miscellaneous utilities. Symbols defined here are used by several library components.
Types | ||
structure type, returned by std::div (typedef) | ||
structure type, returned by std::ldiv (typedef) | ||
(C++11) |
structure type, returned by std::lldiv (typedef) | |
unsigned integer type returned by the sizeof operator (typedef) | ||
Macro constants | ||
indicates program execution status (macro constant) | ||
MB_CUR_MAX |
maximum number of bytes in a multibyte character with the current locale (macro constant) | |
implementation-defined null pointer constant (macro constant) | ||
maximum possible value generated by std::rand (macro constant) | ||
Functions | ||
Process control | ||
causes abnormal program termination (without cleaning up) (function) | ||
causes normal program termination with cleaning up (function) | ||
(C++11) |
causes quick program termination without completely cleaning up (function) | |
(C++11) |
causes normal program termination without cleaning up (function) | |
registers a function to be called on std::exit() invocation (function) | ||
(C++11) |
registers a function to be called on std::quick_exit invocation (function) | |
calls the host environment's command processor (function) | ||
access to the list of environment variables (function) | ||
Memory management | ||
allocates memory (function) | ||
(C++17) |
allocates aligned memory (function) | |
allocates and zeroes memory (function) | ||
expands or shrinks previously allocated memory block (function) | ||
deallocates previously allocated memory (function) | ||
Numeric string conversion | ||
converts a byte string to a floating point value (function) | ||
(C++11) |
converts a byte string to an integer value (function) | |
(C++11) |
converts a byte string to an integer value (function) | |
(C++11) |
converts a byte string to an unsigned integer value (function) | |
converts a byte string to a floating-point value (function) | ||
Wide string manipulation | ||
returns the number of bytes in the next multibyte character (function) | ||
converts the next multibyte character to wide character (function) | ||
converts a wide character to its multibyte representation (function) | ||
converts a narrow multibyte character string to wide string (function) | ||
converts a wide string to narrow multibyte character string (function) | ||
Miscellaneous algorithms and math | ||
generates a pseudo-random number (function) | ||
seeds pseudo-random number generator (function) | ||
sorts a range of elements with unspecified type (function) | ||
searches an array for an element of unspecified type (function) | ||
(C++11) |
computes absolute value of an integral value (|x|) (function) | |
(C++11) |
computes quotient and remainder of integer division (function) |
[edit] Synopsis
namespace std { using size_t = /* see description */; // freestanding using div_t = /* see description */; // freestanding using ldiv_t = /* see description */; // freestanding using lldiv_t = /* see description */; // freestanding } #define NULL /* see description */ // freestanding #define EXIT_FAILURE /* see description */ // freestanding #define EXIT_SUCCESS /* see description */ // freestanding #define RAND_MAX /* see description */ #define MB_CUR_MAX /* see description */ namespace std { // Exposition-only function type aliases extern "C" using /* c-atexit-handler */ = void(); // exposition only extern "C++" using /* atexit-handler */ = void(); // exposition only extern "C" using /* c-compare-pred */ = // exposition only int(const void*, const void*); extern "C++" using /* compare-pred */ = // exposition only int(const void*, const void*); // start and termination [[noreturn]] void abort() noexcept; // freestanding int atexit(/* c-atexit-handler */* func) noexcept; // freestanding int atexit(/* atexit-handler */* func) noexcept; // freestanding int at_quick_exit(/* c-atexit-handler */* func) noexcept; // freestanding int at_quick_exit(/* atexit-handler */* func) noexcept; // freestanding [[noreturn]] void exit(int status); // freestanding [[noreturn]] void _Exit(int status) noexcept; // freestanding [[noreturn]] void quick_exit(int status) noexcept; // freestanding char* getenv(const char* name); int system(const char* string); // C library memory allocation void* aligned_alloc(size_t alignment, size_t size); void* calloc(size_t nmemb, size_t size); void free(void* ptr); void* malloc(size_t size); void* realloc(void* ptr, size_t size); double atof(const char* nptr); int atoi(const char* nptr); long int atol(const char* nptr); long long int atoll(const char* nptr); double strtod(const char* nptr, char** endptr); float strtof(const char* nptr, char** endptr); long double strtold(const char* nptr, char** endptr); long int strtol(const char* nptr, char** endptr, int base); long long int strtoll(const char* nptr, char** endptr, int base); unsigned long int strtoul(const char* nptr, char** endptr, int base); unsigned long long int strtoull(const char* nptr, char** endptr, int base); // multibyte / wide string and character conversion functions int mblen(const char* s, size_t n); int mbtowc(wchar_t* pwc, const char* s, size_t n); int wctomb(char* s, wchar_t wchar); size_t mbstowcs(wchar_t* pwcs, const char* s, size_t n); size_t wcstombs(char* s, const wchar_t* pwcs, size_t n); // C standard library algorithms void* bsearch(const void* key, const void* base, // freestanding size_t nmemb, size_t size, /* c-compare-pred */* compar); void* bsearch(const void* key, const void* base, // freestanding size_t nmemb, size_t size, /* compare-pred */* compar); void qsort(void* base, size_t nmemb, size_t size, // freestanding /* c-compare-pred */* compar); void qsort(void* base, size_t nmemb, size_t size, // freestanding /* compare-pred */* compar); // low-quality random number generation int rand(); void srand(unsigned int seed); // absolute values constexpr int abs(int j); // freestanding constexpr long int abs(long int j); // freestanding constexpr long long int abs(long long int j); // freestanding constexpr /* floating-point-type */ abs(/* floating-point-type */ j); // freestanding-deleted constexpr long int labs(long int j); // freestanding constexpr long long int llabs(long long int j); // freestanding constexpr div_t div(int numer, int denom); // freestanding constexpr ldiv_t div(long int numer, long int denom); // freestanding constexpr lldiv_t div(long long int numer, long long int denom); // freestanding constexpr ldiv_t ldiv(long int numer, long int denom); // freestanding constexpr lldiv_t lldiv(long long int numer, long long int denom); // freestanding }
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 286 | C++98 | the definition of size_t was not provided in <cstdlib>
|
provided |