标准库标头 <stdlib.h>

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C

编译器支持

语言

头文件

类型支持

程序工具

可变参数函数支持

错误处理

动态内存管理

字符串库

算法

数值

日期和时间工具

输入/输出支持

本地化支持

并发支持 (C11)

技术规范

符号索引

 

标准库头

<assert.h> <complex.h> (C99) <ctype.h> <errno.h> <fenv.h> (C99) <float.h> <inttypes.h> (C99)     <iso646.h> (C95) <limits.h> <locale.h> <math.h>

<setjmp.h> <signal.h> <stdalign.h> (C11*) <stdarg.h> <stdatomic.h> (C11)     <stdbit.h> (C23) <stdbool.h> (C99*) <stdckdint.h> (C23) <stddef.h> <stdint.h> (C99) <stdio.h>

<stdlib.h> <stdmchar.h> (C29) <stdnoreturn.h> (C11*) <string.h> <tgmath.h> (C99) <threads.h> (C11) <time.h> <uchar.h> (C11) <wchar.h> (C95) <wctype.h> (C95)

 

此标头是程序支持工具库的一部分，特别是，它提供用于程序终止、内存管理、字符串转换、随机数生成的函数。此标头还提供了一些算法。

函数
abort	引发非正常的程序终止（不清理） (函数)
exit	引发正常的程序终止并清理 (函数)
quick_exit (C11)	引发正常的程序终止但不完全清理 (函数)
_Exit (C99)	引发正常的程序终止但不清理 (函数)
atexit	注册一个要在调用 exit() 时调用的函数 (函数)
at_quick_exit (C11)	注册要在调用 quick_exit 时调用的函数 (函数)
EXIT_SUCCESSEXIT_FAILURE	表示程序的执行结果 (宏常量)

概要

#define __STDC_VERSION_STDLIB_H__ 202311L

// TODO: types and macros

void call_once(once_flag* flag, void (*func)(void));
double atof(const char* nptr);
int atoi(const char* nptr);
long int atol(const char* nptr);
long long int atoll(const char* nptr);
int strfromd(char* restrict s, size_t n, const char* restrict format, double fp);
int strfromf(char* restrict s, size_t n, const char* restrict format, float fp);
int strfroml(char* restrict s, size_t n, const char* restrict format, long double fp);
double strtod(const char* restrict nptr, char** restrict endptr);
float strtof(const char* restrict nptr, char** restrict endptr);
long double strtold(const char* restrict nptr, char** restrict endptr);
long int strtol(const char* restrict nptr, char** restrict endptr, int base);
long long int strtoll(const char* restrict nptr, char** restrict endptr, int base);
unsigned long int strtoul(const char* restrict nptr, char** restrict endptr, int base);
unsigned long long int strtoull(const char* restrict nptr,
                                char** restrict endptr, int base);
int rand(void);
void srand(unsigned int seed);
void* aligned_alloc(size_t alignment, size_t size);
void* calloc(size_t nmemb, size_t size);
void free(void* ptr);
void free_sized(void* ptr, size_t size);
void free_aligned_sized(void* ptr, size_t alignment, size_t size);
void* malloc(size_t size);
void* realloc(void* ptr, size_t size);
[[noreturn]] void abort(void);
int atexit(void (*func)(void));
int at_quick_exit(void (*func)(void));
[[noreturn]] void exit(int status);
[[noreturn]] void _Exit(int status);
char* getenv(const char* name);
[[noreturn]] void quick_exit(int status);
int system(const char* string);
QVoid* bsearch(const void* key, QVoid* base, size_t nmemb, size_t size,
               int (*compar)(const void* , const void* ));
void qsort(void* base, size_t nmemb, size_t size,
           int (*compar)(const void* , const void* ));
int abs(int j);
long int labs(long int j);
long long int llabs(long long int j);
div_t div(int numer, int denom);
ldiv_t ldiv(long int numer, long int denom);
lldiv_t lldiv(long long int numer, long long int denom);
int mblen(const char* s, size_t n);
int mbtowc(wchar_t* restrict pwc, const char* restrict s, size_t n);
int wctomb(char* s, wchar_t wc);
size_t mbstowcs(wchar_t* restrict pwcs, const char* restrict s, size_t n);
size_t wcstombs(char* restrict s, const wchar_t* restrict pwcs, size_t n);
size_t memalignment(const void* p);

仅当实现定义了 __STDC_IEC_60559_DFP__：

int strfromd32(char* restrict s, size_t n, const char* restrict format, _Decimal32 fp);
int strfromd64(char* restrict s, size_t n, const char* restrict format, _Decimal64 fp);
int strfromd128(char* restrict s, size_t n, const char* restrict format, _Decimal128 fp);
_Decimal32 strtod32(const char* restrict nptr, char** restrict endptr);
_Decimal64 strtod64(const char* restrict nptr, char** restrict endptr);
_Decimal128 strtod128(const char* restrict nptr, char** restrict endptr);

仅当实现定义了 __STDC_IEC_60559_TYPES__，而且用户代码在对 stdlib.h 的所有包含之前定义了 __STDC_WANT_IEC_60559_TYPES_EXT__：

#ifdef __STDC_WANT_IEC_60559_TYPES_EXT__
int strfromfN(char* restrict s, size_t n, const char* restrict format, _FloatN fp);
int strfromfNx(char* restrict s, size_t n, const char* restrict format, _FloatNx fp);
int strfromdN(char* restrict s, size_t n, const char* restrict format, _DecimalN fp);
int strfromdNx(char* restrict s, size_t n, const char* restrict format, _DecimalNx fp);
_FloatN strtofN(const char* restrict nptr, char** restrict endptr);
_FloatNx strtofNx(const char* restrict nptr, char** restrict endptr);
_DecimalN strtodN(const char* restrict nptr, char** restrict endptr);
_DecimalNx strtodNx(const char* restrict nptr, char** restrict endptr);
int strfromencfN(char* restrict s, size_t n, const char* restrict format,
                 const unsigned char encptr[restrict static N/8]);
int strfromencdecdN(char* restrict s, size_t n, const char* restrict format,
                    const unsigned char encptr[restrict static N/8]);
int strfromencbindN(char* restrict s, size_t n, const char* restrict format,
                    const unsigned char encptr[restrict static N/8]);
void strtoencfN(unsigned char encptr[restrict static N/8],
                const char* restrict nptr, char** restrict endptr);
void strtoencdecdN(unsigned char encptr[restrict static N/8],
                   const char* restrict nptr, char** restrict endptr);
void strtoencbindN(unsigned char encptr[restrict static N/8],
                   const char* restrict nptr, char** restrict endptr);
#endif

仅当实现定义了 __STDC_LIB_EXT1__，而且用户代码在对 stdio.h 的所有包含之前定义了 __STDC_WANT_LIB_EXT1__：

#if defined(__STDC_WANT_LIB_EXT1__)
constraint_handler_t set_constraint_handler_s(constraint_handler_t handler);
void abort_handler_s(const char* restrict msg, void* restrict ptr, errno_t error);
void ignore_handler_s(const char* restrict msg, void* restrict ptr, errno_t error);
errno_t getenv_s(size_t* restrict len, char* restrict value, rsize_t maxsize,
                 const char* restrict name);
QVoid* bsearch_s(const void* key, QVoid* base, rsize_t nmemb, rsize_t size,
                 int (*compar)(const void* k, const void* y, void* context),
                               void* context);
errno_t qsort_s(void* base, rsize_t nmemb, rsize_t size,
                int (*compar)(const void* x, const void* y, void* context),
                              void* context);
errno_t wctomb_s(int* restrict status, char* restrict s, rsize_t smax,
                 wchar_t wc);
errno_t mbstowcs_s(size_t* restrict retval, wchar_t* restrict dst, rsize_t dstmax,
                   const char* restrict src, rsize_t len);
errno_t wcstombs_s(size_t* restrict retval, char* restrict dst, rsize_t dstmax,
                   const wchar_t* restrict src, rsize_t len);
#endif