Standard library header - cppreference.com (original) (raw)
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.
[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 | provided |