AlgorithmsAlgorithms（算法）bsearchbsearch_sqsortqsort_sAtomic operationsAtomic operations library（原子操作库）ATOMIC_*_LOCK_FREEatomic_compare_exchange_strongatomic_compare_exchange_strong_explicitatomic_compare_exchange_weakatomic_compare_exchange_weak_explicitatomic_exchangeatomic_exchange_explicitatomic_fetch_addatomic_fetch_add_explicitatomic_fetch_andatomic_fetch_and_explicitatomic_fetch_oratomic_fetch_or_explicitatomic_fetch_subatomic_fetch_sub_explicitatomic_fetch_xoratomic_fetch_xor_explicitatomic_flagatomic_flag_clearatomic_flag_clear_explicitATOMIC_FLAG_INITatomic_flag_test_and_setatomic_flag_test_and_set_explicitatomic_initatomic_is_lock_freeatomic_loadatomic_load_explicitatomic_signal_fenceatomic_storeatomic_store_explicitatomic_thread_fence（线程围栏）ATOMIC_VAR_INITkill_dependencymemory_order（内存排序）C keywordsauto（自动存储）break（跳出循环）C keywords（关键词）casecharconst（常量修饰符）continuedefault（预设运算式）dodouble（双精度浮点型）elseenum（枚举类型）extern（全局变量）float（浮点数）forfortrangoto（goto语句）if（if语句）inline（行内函式）intlong（长整型）register（寄存器变量）restrict（ restrict类型限定符）returnshortsignedsizeof（sizeof运算符）static（静态变量）struct（结构体）switch（switch语句）typedef（typedef关键字）union（联合体）unsigned（无符号）void（空类型）volatile（volatile变量）while（while语句）_Alignas_Alignof_Atomic_Bool_Complex_Generic_Imaginary_Noreturn_Static_assert_Thread_localC language#define directive#elif directive#else directive#endif directive#error directive#if directive#ifdef directive#ifndef directive#include directive#line directive#pragma directivealignas（对齐指定符）Alternative operators and tokens（替代运算符和令牌）AnalyzabilityArithmetic operatorsArithmetic typesArray declaration（数组声明）Array initialization（阵列初始化）ASCII ChartAssignment operators（赋值运算符）types（atomic类型限定符）Basic conceptsBit fields（位域）break statementC languageC Operator Precedencecast operatorcharacter constant（字符字面量）Comments（注释符）Comparison operators（比较运算符）compound literals（符合字面量）Conditional inclusion（条件包含）Conformance（一致性）const type qualifier（const 限定符）Constant expressions（常量表达）continue statementDeclarations（声明）do-while loopEnumerations（枚举类型）Escape sequences（转义字符）Expressions（表达式）External and tentative definitions（外部和暂定的定义）File scope（文件范围）floating constant（浮点常量）for loopFunction declarations（函数声明）Function definitions（函数声明）FunctionsGeneric selection泛型选择goto statementIdentifier（标示符）if statementImplicit conversions（隐式转换）Increment/decrement operators（前置/后置操作符）Initialization（初始化）inline function specifier（内联函式）integer constantLifetime（生命期）Logical operators（逻辑运算符）Lookup and name spacesMain function（主函式）Member access operators（会员接入运营商）Memory modelObjects and alignment（字节对齐）Order of evaluation（评估顺序）Other operatorsPhases of translation（翻译阶段）Pointer declarationPreprocessor（预处理）restrict type qualifier（restrict类型限定符）return statementScalar initialization（标量类型初始化）Scope（范围）sizeof operator（sizeof运算符）Statements（陈述）static assert declaration（静态断言声明）Static storage duration（静态存储周期）Storage-class specifiers（存储类说明符）string literals（字符串字面量）Struct and union initialization（结构体与联合体初始化）Struct declaration（结构体声明）switch statementThread storage duration（线程存储时间）TypeType（类型）Typedef declaration（Typedef声明）Undefined behavior（未定义行为）Union declaration（联合体声明）Value categories（值类别）Variadic arguments（变长参数宏）volatile type qualifier（volatile 类型限定符）while loop_Alignof operator_Noreturn function specifierDate and timeasctime（asctime函数）asctime_sclockCLOCKS_PER_SECclock_tctime（ctime函数）ctime_sDate and time utilities（日期和时间库）difftime（计算两个时间的间隔）gmtimegmtime_slocaltimelocaltime_smktime（将时间结构数据转换成经过的秒数的函数）strftime（格式化输出时间函数）timetimespectimespec_gettime_ttmwcsftime（格式化时间宽字符）Dynamic memory managementaligned_allocC memory management library（内存管理库）callocfree（释放动态分配空间的函数）malloc（动态分配内存空间的函数）realloc（重新分配内存空间的函数）Error handlingabort_handler_sassert（断言）constraint_handler_terrno（错误报告）Error handling（错误处理）Error numbers（错误个数）ignore_handler_sset_constraint_handler_sstatic_assertFile input/outputclearerr（清除/复位）fclosefeofferrorfflush（清空文件缓冲区）fgetcfgetposfgetsfgetwcfgetwsFile input/outputfopenfopen_sfprintffprintf_sfputcfputsfputwcfputwsfreadfreopenfreopen_sfscanffscanf_sfseekfsetposftellfwidefwprintffwprintf_sfwritefwscanffwscanf_sgetcgetchargetsgets_sgetwcharperrorprintfprintf_sputcputcharputsputwcputwcharremoverenamerewindscanfscanf_ssetbufsetvbufsnprintfsprintfsscanfsscanf_sswprintfswprintf_sswscanfswscanf_stmpfiletmpfile_stmpnamtmpnam_sungetcungetwcvfprintfvfprintf_svfscanfvfscanf_svfwprintfvfwprintf_svfwscanfvfwscanf_svprintfvprintf_svscanfvscanf_svsnprintfvsprintfvsscanfvsscanf_svswprintfvswprintf_svswscanfvswscanf_svwprintfvwprintf_svwscanfvwscanf_swprintfwprintf_swscanfwscanf_sLocalization supportlconvLC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIMElocaleconvLocalization supportsetlocaleNumericsabsacosacosfacoshacoshfacoshlacoslasinasinfasinhasinhfasinhlasinlatanatan2atan2fatan2latanfatanhatanhfatanhlatanlcabscabsfcabslcacoscacosfcacoshcacoshfcacoshlcacoslcargcargfcarglcasincasinfcasinhcasinhfcasinhlcasinlcatancatanfcatanhcatanhfcatanhlcatanlcbrtcbrtfcbrtlccosccosfccoshccoshfccoshlccoslceilceilfceillcexpcexpfcexplcimagcimagfcimaglclogclogfcloglCMPLXCMPLXFCMPLXLCommon mathematical functionscomplexComplex number arithmeticconjconjfconjlcopysigncopysignfcopysignlcoscosfcoshcoshfcoshlcoslcpowcpowfcpowlcprojcprojfcprojlcrealcrealfcreallcsincsinfcsinhcsinhfcsinhlcsinlcsqrtcsqrtfcsqrtlctanctanfctanhctanhfctanhlctanldivdouble_terferfcerfcferfclerfferflexpexp2exp2fexp2lexpfexplexpm1expm1fexpm1lfabsfabsffabslfdimfeclearexceptfegetenvfegetexceptflagfegetroundfeholdexceptferaiseexceptfesetenvfesetexceptflagfesetroundfetestexceptfeupdateenvFE_ALL_EXCEPTFE_DFL_ENVFE_DIVBYZEROFE_DOWNWARDFE_INEXACTFE_INVALIDFE_OVERFLOWFE_TONEARESTFE_TOWARDZEROFE_UNDERFLOWFE_UPWARDFloating-point environmentfloat_tfloorfloorffloorlfmafmaffmalfmaxfmaxffmaxlfminfminffminlfmodfmodffmodlfpclassifyFP_INFINITEFP_NANFP_NORMALFP_SUBNORMALFP_ZEROfrexpfrexpffrexplHUGE_VALHUGE_VALFHUGE_VALLhypothypotfhypotlIilogbilogbfilogblimaginaryimaxabsimaxdivINFINITYisfiniteisgreaterisgreaterequalisinfislessislessequalislessgreaterisnanisnormalisunorderedlabsldexpldexpfldexplldivlgammalgammaflgammalllabslldivllrintllrintfllrintlllroundllroundfllroundlloglog10log10flog10llog1plog1pflog1pllog2log2flog2llogblogbflogbllogflogllrintlrintflrintllroundlroundflroundlMATH_ERREXCEPTmath_errhandlingMATH_ERRNOmodfmodffmodflnanNANnanfnanlnearbyintnearbyintfnearbyintlnextafternextafterfnextafterlnexttowardnexttowardfnexttowardlNumericspowpowfpowlPseudo-random number generationrandRAND_MAXremainderremainderfremainderlremquoremquofremquolrintrintfrintlroundroundfroundlscalblnscalblnfscalblnlscalbnscalbnfscalbnlsignbitsinsinfsinhsinhfsinhlsinlsqrtsqrtfsqrtlsrandtantanftanhtanhftanhltanltgammatgammaftgammaltrunctruncftrunclType-generic math_Complex_I_Imaginary_IProgram supportabortatexitat_quick_exitexitEXIT_FAILUREEXIT_SUCCESSgetenvgetenv_sjmp_buflongjmpProgram support utilitiesquick_exitraisesetjmpSIGABRTSIGFPESIGILLSIGINTsignalSIGSEGVSIGTERMsig_atomic_tSIG_DFLSIG_ERRSIG_IGNsystem_ExitStringsatofatoiatolatollbtowcc16rtombc32rtombchar16_tchar32_tisalnumisalphaisblankiscntrlisdigitisgraphislowerisprintispunctisspaceisupperiswalnumiswalphaiswblankiswcntrliswctypeiswdigitiswgraphiswloweriswprintiswpunctiswspaceiswupperiswxdigitisxdigitmblenmbrlenmbrtoc16mbrtoc32mbrtowcmbsinitmbsrtowcsmbsrtowcs_smbstate_tmbstowcsmbstowcs_smbtowcmemchrmemcmpmemcpymemcpy_smemmovememmove_smemsetmemset_sNull-terminated byte stringsNull-terminated multibyte stringsNull-terminated wide stringsstrcatstrcat_sstrchrstrcmpstrcollstrcpystrcpy_sstrcspnstrerrorstrerrorlen_sstrerror_sStrings librarystrlenstrncatThread supportcall_oncecnd_broadcastcnd_destroycnd_initcnd_signalcnd_timedwaitcnd_waitmtx_destroymtx_initmtx_lockmtx_plainmtx_recursivemtx_timedmtx_timedlockmtx_trylockmtx_unlockonce_flagONCE_FLAG_INITthrd_busythrd_createthrd_currentthrd_detachthrd_equalthrd_errorthrd_exitthrd_jointhrd_nomemthrd_sleepthrd_successthrd_timedoutthrd_yieldThread support librarythread_localtss_createtss_deleteTSS_DTOR_ITERATIONStss_gettss_setType supportBoolean type support libraryFixed width integer typesFLT_EVAL_METHODFLT_ROUNDSmax_align_tNULLNumeric limitsoffsetofptrdiff_tsize_tType supportVariadic functionsVariadic functionsva_argva_copyva_endva_listva_start
©
本文档使用
php.cn手册 发布
文字
库类型的限制
| 在头文件<stdint.h>中定义 |
|:----|
| PTRDIFF_MIN（C99）| ptrdiff_t类型（宏常量）|的对象的最小值
| PTRDIFF_MAX（C99）| ptrdiff_t类型（宏常量）|的对象的最大值
| SIZE_MAX（C99）| size_t类型（宏常量）|的对象的最大值
| SIG_ATOMIC_MIN（C99）| sig_atomic_t类型（宏常量）|的对象的最小值
| SIG_ATOMIC_MAX（C99）| sig_atomic_t类型（宏常量）|的对象的最大值
| 在头文件<wchar.h>中定义 |
| WCHAR_MIN（C99）| wchar_t类型（宏常量）|的对象的最小值
| WCHAR_MAX（C99）| wchar_t类型（宏常量）|的对象的最大值
| WINT_MIN（C99）| wint_t类型（宏常量）|的对象的最小值
| WINT_MAX（C99）| wint_t类型（宏常量）|的对象的最大值
例
#include <stdio.h>#include <stdint.h>#include <wchar.h>
int main(void){ printf("PTRDIFF_MIN = %td\n", PTRDIFF_MIN); printf("PTRDIFF_MAX = %+td\n", PTRDIFF_MAX); printf("SIZE_MAX = %zu\n", SIZE_MAX); printf("SIG_ATOMIC_MIN = %+jd\n",(intmax_t)SIG_ATOMIC_MIN); printf("SIG_ATOMIC_MAX = %+jd\n",(intmax_t)SIG_ATOMIC_MAX); printf("WCHAR_MIN = %+jd\n",(intmax_t)WCHAR_MIN); printf("WCHAR_MAX = %+jd\n",(intmax_t)WCHAR_MAX); printf("WINT_MIN = %jd\n", (intmax_t)WINT_MIN); printf("WINT_MAX = %jd\n", (intmax_t)WINT_MAX);}可能的输出：
PTRDIFF_MIN = -9223372036854775808PTRDIFF_MAX = +9223372036854775807SIZE_MAX = 18446744073709551615SIG_ATOMIC_MIN = -2147483648SIG_ATOMIC_MAX = +2147483647WCHAR_MIN = -2147483648WCHAR_MAX = +2147483647WINT_MIN = 0WINT_MAX = 4294967295
整数类型的限制
| 在头文件<limits.h>中定义 |
|:----|
| CHAR_BIT | 字节中的位数（宏常量）|
| MB_LEN_MAX | 多字节字符中的最大字节数（宏常量）|
| CHAR_MIN | char（宏常量）|的最小值
| CHAR_MAX | char（宏常量）|的最大值
| SCHAR_MINSHRT_MININT_MINLONG_MINLLONG_MIN（C99）| signed char，short，int，long和long long的最小值（宏常量）|
| SCHAR_MAXSHRT_MAXINT_MAXLONG_MAXLLONG_MAX（C99）| signed char，short，int，long和long long的最大值（宏常量）|
| UCHAR_MAXUSHRT_MAXUINT_MAXULONG_MAXULLONG_MAX（C99）| unsigned char，unsigned short，unsigned int，unsigned long和unsigned long long的最大值（宏常量）|
例
#include <stdio.h>#include <limits.h>
int main(void){
printf("CHAR_BIT = %d\n", CHAR_BIT); printf("MB_LEN_MAX = %d\n", MB_LEN_MAX); printf("\n");
printf("CHAR_MIN = %+d\n", CHAR_MIN); printf("CHAR_MAX = %+d\n", CHAR_MAX); printf("SCHAR_MIN = %+d\n", SCHAR_MIN); printf("SCHAR_MAX = %+d\n", SCHAR_MAX); printf("UCHAR_MAX = %u\n", UCHAR_MAX); printf("\n");
printf("SHRT_MIN = %+d\n", SHRT_MIN); printf("SHRT_MAX = %+d\n", SHRT_MAX); printf("USHRT_MAX = %u\n", USHRT_MAX); printf("\n");
printf("INT_MIN = %+d\n", INT_MIN); printf("INT_MAX = %+d\n", INT_MAX); printf("UINT_MAX = %u\n", UINT_MAX); printf("\n");
printf("LONG_MIN = %+ld\n", LONG_MIN); printf("LONG_MAX = %+ld\n", LONG_MAX); printf("ULONG_MAX = %lu\n", ULONG_MAX); printf("\n");
printf("LLONG_MIN = %+lld\n", LLONG_MIN); printf("LLONG_MAX = %+lld\n", LLONG_MAX); printf("ULLONG_MAX = %llu\n", ULLONG_MAX); printf("\n");}可能的输出：
CHAR_BIT = 8MB_LEN_MAX = 16 CHAR_MIN = -128CHAR_MAX = +127SCHAR_MIN = -128SCHAR_MAX = +127UCHAR_MAX = 255 SHRT_MIN = -32768SHRT_MAX = +32767USHRT_MAX = 65535 INT_MIN = -2147483648INT_MAX = +2147483647UINT_MAX = 4294967295 LONG_MIN = -9223372036854775808LONG_MAX = +9223372036854775807ULONG_MAX = 18446744073709551615 LLONG_MIN = -9223372036854775808LLONG_MAX = +9223372036854775807ULLONG_MAX = 18446744073709551615
浮点类型的限制
| 在头文件<float.h> |中定义
|:----|
| FLT_RADIX | 所有三个浮点类型（宏常量）|的表示使用的基数（整数基数）
| DECIMAL_DIG（C99）| 从long double转换为decimal，至少DECIMAL_DIG digits并返回long double是标识转换：这是序列化/反序列化long double（宏常量）所需的十进制精度。
| FLT_DECIMAL_DIGDBL_DECIMAL_DIGLDBL_DECIMAL_DIG（C11）| 从float / double / long double到decimal的转换至少为FLT_DECIMAL_DIG / DBL_DECIMAL_DIG / LDBL_DECIMAL_DIG数字，后面是标识转换：这是序列化/反序列化浮点值所需的十进制精度。分别定义为至少6,10和10，或者IEEE浮点数为9，IEEE双精度为17。（另请参阅C ++ analog max_digits10）（宏常量）|
| FLT_MINDBL_MINLDBL_MIN | float，double和long double的最小值，标准化值，正值分别为（宏常量）|
| FLT_TRUE_MINDBL_TRUE_MINLDBL_TRUE_MIN（C11）| float，double和long double的最小正值分别为（宏常量）|
| FLT_MAXDBL_MAXLDBL_MAX | float，double和long double的最大值（宏常量）|
| FLT_EPSILONDBL_EPSILONLDBL_EPSILON | 1.0和浮点型，双精度型和长双精度型的下一个可表示值之间的差值（宏常数）|
| FLT_DIGDBL_DIGLDBL_DIG | 保证保留在文本中的小数位数 - > float / double / long double - >文本往返不会因四舍五入或溢出而发生变化（详见C ++模拟位数10）（宏常量）|
| FLT_MANT_DIGDBL_MANT_DIGLDBL_MANT_DIG | 浮点尾数中可以表示的基FLT_RADIX数字的数量，并且可以分别表示浮点，双精度和长精度的精度（宏常数）|
| FLT_MIN_EXPDBL_MIN_EXPLDBL_MIN_EXP | 最小的负整数，使FLT_RADIX小于该整数的幂乘1是一个标准化的float，double和long double（宏常量）|
| FLT_MIN_10_EXPDBL_MIN_10_EXPLDBL_MIN_10_EXP | 最小负整数，使得10次幂小于该整数时，分别为标准化的float，double和long double（宏常量）|
| FLT_MAX_EXPDBL_MAX_EXPLDBL_MAX_EXP | 最大正整数，使得FLT_RADIX由小于该整数的幂乘1产生一个归一化的float，double和long double（宏常量）|
| FLT_MAX_10_EXPDBL_MAX_10_EXPLDBL_MAX_10_EXP | 最大正整数，使得由小于该整数的幂次提升的10个是分别为标准化的float，double和long double（宏常量）|
| FLT_ROUNDS | 四舍五入浮点运算模式，等于float_round_style（宏常量）|
| FLT_EVAL_METHOD（C99）| 对于中间结果使用扩展精度：0未使用，1使用double来代替float，2使用long double（宏常量）|
| FLT_HAS_SUBNORMDBL_HAS_SUBNORMLDBL_HAS_SUBNORM（C11）| 该类型是否支持低于正常（非正常）数字：-1不确定，0不存在，1存在（宏常量）|
例
#include <stdio.h>#include <float.h> #include <math.h>
int main(void){ printf("FLT_RADIX = %d\n", FLT_RADIX); printf("DECIMAL_DIG = %d\n", DECIMAL_DIG); printf("FLT_MIN = %e\n", FLT_MIN); printf("FLT_MAX = %e\n", FLT_MAX); printf("FLT_EPSILON = %e\n", FLT_EPSILON); printf("FLT_DIG = %d\n", FLT_DIG); printf("FLT_MANT_DIG = %d\n", FLT_MANT_DIG); printf("FLT_MIN_EXP = %d\n", FLT_MIN_EXP); printf("FLT_MIN_10_EXP = %d\n", FLT_MIN_10_EXP); printf("FLT_MAX_EXP = %d\n", FLT_MAX_EXP); printf("FLT_MAX_10_EXP = %d\n", FLT_MAX_10_EXP); printf("FLT_ROUNDS = %d\n", FLT_ROUNDS); printf("FLT_EVAL_METHOD = %d\n", FLT_EVAL_METHOD); printf("FLT_HAS_SUBNORM = %d\n", FLT_HAS_SUBNORM);}可能的输出：
FLT_RADIX = 2DECIMAL_DIG = 37FLT_MIN = 1.175494e-38FLT_MAX = 3.402823e+38FLT_EPSILON = 1.192093e-07FLT_DIG = 6FLT_MANT_DIG = 24FLT_MIN_EXP = -125FLT_MIN_10_EXP = -37FLT_MAX_EXP = 128FLT_MAX_10_EXP = 38FLT_ROUNDS = 1FLT_EVAL_METHOD = 1FLT_HAS_SUBNORM = 1