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vscanf_s vsnprintf vsprintf vsscanf vsscanf_s vswprintf vswprintf_s vswscanf vswscanf_s vwprintf vwprintf_s vwscanf vwscanf_s wprintf wprintf_s wscanf wscanf_s Localization support lconv LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME localeconv Localization support setlocale Numerics abs acos acosf acosh acoshf acoshl acosl asin asinf asinh asinhf asinhl asinl atan atan2 atan2f atan2l atanf atanh atanhf atanhl atanl cabs cabsf cabsl cacos cacosf cacosh cacoshf cacoshl cacosl carg cargf cargl casin casinf casinh casinhf casinhl casinl catan catanf catanh catanhf catanhl catanl cbrt cbrtf cbrtl ccos ccosf ccosh ccoshf ccoshl ccosl ceil ceilf ceill cexp cexpf cexpl cimag cimagf cimagl clog clogf clogl CMPLX CMPLXF CMPLXL Common mathematical functions complex Complex number arithmetic conj conjf conjl copysign copysignf copysignl cos cosf cosh coshf coshl cosl cpow cpowf cpowl cproj cprojf cprojl creal crealf creall csin csinf csinh csinhf csinhl csinl csqrt csqrtf csqrtl ctan ctanf ctanh ctanhf ctanhl ctanl div double_t erf erfc erfcf erfcl erff erfl exp exp2 exp2f exp2l expf expl expm1 expm1f expm1l fabs fabsf fabsl fdim feclearexcept fegetenv fegetexceptflag fegetround feholdexcept feraiseexcept fesetenv fesetexceptflag fesetround fetestexcept feupdateenv FE_ALL_EXCEPT FE_DFL_ENV FE_DIVBYZERO FE_DOWNWARD FE_INEXACT FE_INVALID FE_OVERFLOW FE_TONEAREST FE_TOWARDZERO FE_UNDERFLOW FE_UPWARD Floating-point environment float_t floor floorf floorl fma fmaf fmal fmax fmaxf fmaxl fmin fminf fminl fmod fmodf fmodl fpclassify FP_INFINITE FP_NAN FP_NORMAL FP_SUBNORMAL FP_ZERO frexp frexpf frexpl HUGE_VAL HUGE_VALF HUGE_VALL hypot hypotf hypotl I ilogb ilogbf ilogbl imaginary imaxabs imaxdiv INFINITY isfinite isgreater isgreaterequal isinf isless islessequal islessgreater isnan isnormal isunordered labs ldexp ldexpf ldexpl ldiv lgamma lgammaf lgammal llabs lldiv llrint llrintf llrintl llround llroundf llroundl log log10 log10f log10l log1p log1pf log1pl log2 log2f log2l logb logbf logbl logf logl lrint lrintf lrintl lround lroundf lroundl MATH_ERREXCEPT math_errhandling MATH_ERRNO modf modff modfl nan NAN nanf nanl nearbyint nearbyintf nearbyintl nextafter nextafterf nextafterl nexttoward nexttowardf nexttowardl Numerics pow powf powl Pseudo-random number generation rand RAND_MAX remainder remainderf remainderl remquo remquof remquol rint rintf rintl round roundf roundl scalbln scalblnf scalblnl scalbn scalbnf scalbnl signbit sin sinf sinh sinhf sinhl sinl sqrt sqrtf sqrtl srand tan tanf tanh tanhf tanhl tanl tgamma tgammaf tgammal trunc truncf truncl Type-generic math _Complex_I _Imaginary_I Program support abort atexit at_quick_exit exit EXIT_FAILURE EXIT_SUCCESS getenv getenv_s jmp_buf longjmp Program support utilities quick_exit raise setjmp SIGABRT SIGFPE SIGILL SIGINT signal SIGSEGV SIGTERM sig_atomic_t SIG_DFL SIG_ERR SIG_IGN system _Exit Strings atof atoi atol atoll btowc c16rtomb c32rtomb char16_t char32_t isalnum isalpha isblank iscntrl isdigit isgraph islower isprint ispunct isspace isupper iswalnum iswalpha iswblank iswcntrl iswctype iswdigit iswgraph iswlower iswprint iswpunct iswspace iswupper iswxdigit isxdigit mblen mbrlen mbrtoc16 mbrtoc32 mbrtowc mbsinit mbsrtowcs mbsrtowcs_s mbstate_t mbstowcs mbstowcs_s mbtowc memchr memcmp memcpy memcpy_s memmove memmove_s memset memset_s Null-terminated byte strings Null-terminated multibyte strings Null-terminated wide strings strcat strcat_s strchr strcmp strcoll strcpy strcpy_s strcspn strerror strerrorlen_s strerror_s Strings library strlen strncat Thread support call_once cnd_broadcast cnd_destroy cnd_init cnd_signal cnd_timedwait cnd_wait mtx_destroy mtx_init mtx_lock mtx_plain mtx_recursive mtx_timed mtx_timedlock mtx_trylock mtx_unlock once_flag ONCE_FLAG_INIT thrd_busy thrd_create thrd_current thrd_detach thrd_equal thrd_error thrd_exit thrd_join thrd_nomem thrd_sleep thrd_success thrd_timedout thrd_yield Thread support library thread_local tss_create tss_delete TSS_DTOR_ITERATIONS tss_get tss_set Type support Boolean type support library Fixed width integer types FLT_EVAL_METHOD FLT_ROUNDS max_align_t NULL Numeric limits offsetof ptrdiff_t size_t Type support Variadic functions Variadic functions va_arg va_copy va_end va_list va_start
characters

在頭文件<wchar.h>中定義




(1)


int wscanf（const wchar_t * format，...）;

（自C95以來）（直到C99）


int wscanf（const wchar_t * restrict format，...）;

（自C99以來）



(2)


int fwscanf（FILE * stream，const wchar_t * format，...）;

（自C95以來）（直到C99）


int fwscanf（FILE * restrict stream，const wchar_t * restrict format，...）;

（自C99以來）



(3)


int swscanf（const wchar_t * buffer，const wchar_t * format，...）;

（自C95以來）（直到C99）


int swscanf（const wchar_t * restrict buffer，const wchar_t * restrict format，...）;

（自C99以來）


int wscanf_s（const wchar_t * restrict format，...）;

(4)

（自C11以來）

int fwscanf_s（FILE * restrict stream，const wchar_t * restrict format，...）;

(5)

（自C11以來）

int swscanf_s（const wchar_t * restrict s，const wchar_t * restrict format，...）;

(6)

（自C11以來）

從各種來源讀取數(shù)據(jù)，根據(jù)其解釋并將format結(jié)果存儲到給定位置。

1）從中讀取數(shù)據(jù)stdin。

2）從文件流中讀取數(shù)據(jù)stream。

3）從空終止的寬字符串中讀取數(shù)據(jù)buffer。到達(dá)字符串的末尾等同于達(dá)到文件結(jié)束條件fwscanf

4-6）同（1-3），所不同的是%c，%s和%[轉(zhuǎn)換說明每個期望兩個參數(shù)（通常的指針和類型的值rsize_t指示所述接收陣列的大小，其可以是1附有％LC讀取時成一個單一的寬字符），除了在運行時檢測到以下錯誤并調(diào)用當(dāng)前安裝的約束處理函數(shù)：

  • 指針類型的任何參數(shù)都是空指針

  • format，stream或者buffer是空指針

  • ％c，％s或％[，加上終止空字符，將會超過為每個轉(zhuǎn)換說明符提供的第二個（rsize_t）參數(shù)所寫的字符數(shù)

  • 可選地，還有任何其他可檢測到的錯誤，例如未知的轉(zhuǎn)換說明符

由于所有的邊界檢查功能，wscanf_s，fwscanf_s，和swscanf_s僅保證可供如果__STDC_LIB_EXT1__由實現(xiàn)所定義，并且如果用戶定義__STDC_WANT_LIB_EXT1__的整數(shù)常數(shù)1，包括之前<wchar.h>。

參數(shù)

流

-

輸入文件流從中讀取



















































































緩沖

-

指向以空字符結(jié)尾的寬字符串讀取的指針



















































































格式

-

pointer to a null-terminated wide string specifying how to read the input. The format string consists of   non-whitespace wide characters except %: each such character in the format string consumes exactly one identical character from the input stream, or causes the function to fail if the next character on the stream does not compare equal.   whitespace characters: any single whitespace character in the format string consumes all available consecutive whitespace characters from the input (determined as if by calling iswspace in a loop). Note that there is no difference between "\n", " ", "\t\t", or other whitespace in the format string.   conversion specifications. Each conversion specification has the following format:    introductory % character   (optional) assignment-suppressing character *. If this option is present, the function does not assign the result of the conversion to any receiving argument.   (optional) integer number (greater than zero) that specifies maximum field width, that is, the maximum number of characters that the function is allowed to consume when doing the conversion specified by the current conversion specification. Note that %s and %[ may lead to buffer overflow if the width is not provided.   (optional) length modifier that specifies the size of the receiving argument, that is, the actual destination type. This affects the conversion accuracy and overflow rules. The default destination type is different for each conversion type (see table below).   conversion format specifier         The following format specifiers are available:    Conversion specifier   Explanation   Argument type     length modifier   hh (C99).   h   (none)   l   ll (C99).   j (C99).   z (C99).   t (C99).   L     %   matches literal %   N/A   N/A   N/A   N/A   N/A   N/A   N/A   N/A   N/A     c    matches a character or a sequence of characters  If a width specifier is used, matches exactly width wide characters (the argument must be a pointer to an array with sufficient room). Unlike %s and %[, does not append the null character to the array.   N/A   N/A   char*   wchar_t*   N/A   N/A   N/A   N/A   N/A     s    matches a sequence of non-whitespace characters (a string)  If width specifier is used, matches up to width or until the first whitespace character, whichever appears first. Always stores a null character in addition to the characters matched (so the argument array must have room for at least width+1 characters).     set   matches a non-empty sequence of character from set of characters.  If the first character of the set is ^, then all characters not in the set are matched. If the set begins with ] or ^] then the ] character is also included into the set. It is implementation-defined whether the character - in the non-initial position in the scanset may be indicating a range, as in 0-9. If width specifier is used, matches only up to width. Always stores a null character in addition to the characters matched (so the argument array must have room for at least width+1 characters).     d   matches a decimal integer.  The format of the number is the same as expected by wcstol() with the value 10 for the base argument.    signed char* or unsigned char*     signed short* or unsigned short*     signed int* or unsigned int*     signed long* or unsigned long*     signed long long* or unsigned long long*     intmax_t* or uintmax_t*    size_t*   ptrdiff_t*   N/A     i   matches an integer.  The format of the number is the same as expected by wcstol() with the value 0 for the base argument (base is determined by the first characters parsed).     u   matches an unsigned decimal integer.  The format of the number is the same as expected by wcstoul() with the value 10 for the base argument.     o   matches an unsigned octal integer.  The format of the number is the same as expected by wcstoul() with the value 8 for the base argument.     x, X   matches an unsigned hexadecimal integer.  The format of the number is the same as expected by wcstoul() with the value 16 for the base argument.     n   returns the number of characters read so far.  No input is consumed. Does not increment the assignment count. If the specifier has assignment-suppressing operator defined, the behavior is undefined.     a, A(C99) e, E f, F g, G   matches a floating-point number.  The format of the number is the same as expected by wcstof().   N/A   N/A   float*   double*   N/A   N/A   N/A   N/A   long double*     p   matches implementation defined character sequence defining a pointer.  printf family of functions should produce the same sequence using %p format specifier.   N/A   N/A   void**   N/A   N/A   N/A   N/A   N/A   N/A    For every conversion specifier other than n, the longest sequence of input characters which does not exceed any speci?ed ?eld width and which either is exactly what the conversion specifier expects or is a prefix of a sequence it would expect, is what's consumed from the stream. The ?rst character, if any, after this consumed sequence remains unread. If the consumed sequence has length zero or if the consumed sequence cannot be converted as specified above, the matching failure occurs unless end-of-?le, an encoding error, or a read error prevented input from the stream, in which case it is an input failure. All conversion specifiers other than [, c, and n consume and discard all leading whitespace characters (determined as if by calling iswspace) before attempting to parse the input. These consumed characters do not count towards the specified maximum field width. If the length specifier l is not used, the conversion specifiers c, s, and [ perform wide-to-multibyte character conversion as if by calling wcrtomb() with an mbstate_t object initialized to zero before the first character is converted. The conversion specifiers s and [ always store the null terminator in addition to the matched characters. The size of the destination array must be at least one greater than the specified field width. The use of %s or %[, without specifying the destination array size, is as unsafe as gets. The correct conversion specifications for the fixed-width integer types (int8_t, etc) are defined in the header <inttypes.h> (although SCNdMAX, SCNuMAX, etc is synonymous with %jd, %ju, etc). There is a sequence point after the action of each conversion specifier; this permits storing multiple fields in the same "sink" variable. When parsing an incomplete floating-point value that ends in the exponent with no digits, such as parsing "100er" with the conversion specifier %f, the sequence "100e" (the longest prefix of a possibly valid floating-point number) is consumed, resulting in a matching error (the consumed sequence cannot be converted to a floating-point number), with "r" remaining. Existing implementations do not follow this rule and roll back to consume only "100", leaving "er", e.g. glibc bug 1765.

Conversion specifier

Explanation

Argument type

length modifier

hh (C99).

h

(none)

l

ll (C99).

j (C99).

z (C99).

t (C99).

L

%

matches literal %

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

c

matches a character or a sequence of characters  If a width specifier is used, matches exactly width wide characters (the argument must be a pointer to an array with sufficient room). Unlike %s and %[, does not append the null character to the array.

N/A

N/A

char*

wchar_t*

N/A

N/A

N/A

N/A

N/A

s

matches a sequence of non-whitespace characters (a string)  If width specifier is used, matches up to width or until the first whitespace character, whichever appears first. Always stores a null character in addition to the characters matched (so the argument array must have room for at least width+1 characters).

set

matches a non-empty sequence of character from set of characters.  If the first character of the set is ^, then all characters not in the set are matched. If the set begins with ] or ^] then the ] character is also included into the set. It is implementation-defined whether the character - in the non-initial position in the scanset may be indicating a range, as in 0-9. If width specifier is used, matches only up to width. Always stores a null character in addition to the characters matched (so the argument array must have room for at least width+1 characters).

d

matches a decimal integer.  The format of the number is the same as expected by wcstol() with the value 10 for the base argument.

signed char* or unsigned char*

signed short* or unsigned short*

signed int* or unsigned int*

signed long* or unsigned long*

signed long long* or unsigned long long*

intmax_t* or uintmax_t*

size_t*

ptrdiff_t*

N/A

i

matches an integer.  The format of the number is the same as expected by wcstol() with the value 0 for the base argument (base is determined by the first characters parsed).

u

matches an unsigned decimal integer.  The format of the number is the same as expected by wcstoul() with the value 10 for the base argument.

o

matches an unsigned octal integer.  The format of the number is the same as expected by wcstoul() with the value 8 for the base argument.

x, X

matches an unsigned hexadecimal integer.  The format of the number is the same as expected by wcstoul() with the value 16 for the base argument.

n

returns the number of characters read so far.  No input is consumed. Does not increment the assignment count. If the specifier has assignment-suppressing operator defined, the behavior is undefined.

a, A(C99) e, E f, F g, G

matches a floating-point number.  The format of the number is the same as expected by wcstof().

N/A

N/A

float*

double*

N/A

N/A

N/A

N/A

long double*

p

matches implementation defined character sequence defining a pointer.  printf family of functions should produce the same sequence using %p format specifier.

N/A

N/A

void**

N/A

N/A

N/A

N/A

N/A

N/A

Conversion specifier

Explanation

Argument type



















































































length modifier

hh (C99).

h

(none)

l

ll (C99).

j (C99).

z (C99).

t (C99).

L












































































%

matches literal %

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A











































































c

matches a character or a sequence of characters  If a width specifier is used, matches exactly width wide characters (the argument must be a pointer to an array with sufficient room). Unlike %s and %[, does not append the null character to the array.

N/A

N/A

char*

wchar_t*

N/A

N/A

N/A

N/A

N/A











































































s

matches a sequence of non-whitespace characters (a string)  If width specifier is used, matches up to width or until the first whitespace character, whichever appears first. Always stores a null character in addition to the characters matched (so the argument array must have room for at least width+1 characters).




















































































set

matches a non-empty sequence of character from set of characters.  If the first character of the set is ^, then all characters not in the set are matched. If the set begins with ] or ^] then the ] character is also included into the set. It is implementation-defined whether the character - in the non-initial position in the scanset may be indicating a range, as in 0-9. If width specifier is used, matches only up to width. Always stores a null character in addition to the characters matched (so the argument array must have room for at least width+1 characters).




















































































d

matches a decimal integer.  The format of the number is the same as expected by wcstol() with the value 10 for the base argument.

signed char* or unsigned char*

signed short* or unsigned short*

signed int* or unsigned int*

signed long* or unsigned long*

signed long long* or unsigned long long*

intmax_t *或uintmax_t *

為size_t *

ptrdiff_t的*

N / A











































































一世

匹配一個整數(shù)。數(shù)字的格式與wcstol（）預(yù)期的相同，基本參數(shù)的值為0（基數(shù)由解析的第一個字符決定）。




















































































在

匹配一個無符號的十進(jìn)制整數(shù)。數(shù)字的格式與wcstoul（）所預(yù)期的相同，基本參數(shù)的值為10。




















































































該

匹配一個無符號的八進(jìn)制整數(shù)。該數(shù)字的格式與wcstoul（）所預(yù)期的基本參數(shù)的值為8相同。




















































































x，X

匹配一個無符號的十六進(jìn)制整數(shù)。數(shù)字的格式與wcstoul（）所預(yù)期的相同，基本參數(shù)的值為16。




















































































?

返回迄今閱讀的字符數(shù)。沒有輸入被消耗。不增加分配計數(shù)。如果說明符具有定義的分配抑制運算符，則行為是未定義的。




















































































a，A（C99）e，E f，F(xiàn) g，G

匹配一個浮點數(shù)。數(shù)字的格式與wcstof（）的預(yù)期相同。

N / A

N / A

浮動*

雙*

N / A

N / A

N / A

N / A

長雙*











































































p

匹配定義指針的實現(xiàn)定義的字符序列。printf系列函數(shù)應(yīng)該使用％p格式說明符產(chǎn)生相同的序列。

N / A

N / A

無效**

N / A

N / A

N / A

N / A

N / A

N / A











































































...

-

接收參數(shù)



















































































  • 非空格寬字符除外%：格式字符串中的每個這樣的字符都只消耗輸入流中的一個完全相同的字符，或者如果流中的下一個字符不相等，則會導(dǎo)致函數(shù)失敗。

  • 空白字符：格式字符串中的任何單個空白字符都會消耗輸入中所有可用的連續(xù)空白字符（如同通過調(diào)用iswspace循環(huán)來確定）。請注意，有沒有什么區(qū)別"\n"，" "，"\t\t"在格式字符串或其他空白。

  • 轉(zhuǎn)換規(guī)格。每個轉(zhuǎn)換規(guī)范具有以下格式：

    • 介紹%人物

    • （可選）分配抑制字符*。如果存在此選項，則函數(shù)不會將轉(zhuǎn)換結(jié)果分配給任何接收參數(shù)。

    • （可選）指定最大字段寬度的整數(shù)數(shù)字（大于零），即該函數(shù)在執(zhí)行由當(dāng)前轉(zhuǎn)換規(guī)范指定的轉(zhuǎn)換時允許使用的最大字符數(shù)。請注意，如果未提供寬度，％s和％[可能會導(dǎo)致緩沖區(qū)溢出。

    • （可選）長度修飾符，用于指定接收參數(shù)的大小，即實際的目標(biāo)類型。這會影響轉(zhuǎn)換精度和溢出規(guī)則。每種轉(zhuǎn)換類型的默認(rèn)目標(biāo)類型都不相同（請參閱下表）。

    • 轉(zhuǎn)換格式說明符

以下格式說明符可用：

Conversion

說明符說明參數(shù)類型長度修飾符    hh（C99）。

h   (none)   l   ll (C99).

j (C99).

z (C99).

t (C99).

L %   匹配字面%   N / AN / AN / AN / AN / AN / AN / AN / AN / A      c    一個匹配字符或序列字符如果使用寬度說明，完全匹配寬度寬字符（參數(shù)必須是一個指向陣列有足夠的空間）。與％s和％[不同，不會將空字符追加到數(shù)組。

N/A   N/A   char*

wchar_t*

N / AN / AN / AN / AN / A      s    匹配非空白字符序列（字符串）如果使用寬度說明符，則匹配寬度或直到第一個空白字符，以先出現(xiàn)者為準(zhǔn)。除了匹配的字符外，總是存儲一個空字符（所以參數(shù)數(shù)組必須至少有寬度+ 1個字符的空間）。

 `[`set`]`   matches a non-empty sequence of character from set of characters.  If the first character of the set is `^`, then all characters not in the set are matched. If the set begins with `]` or `^]` then the `]` character is also included into the set. It is implementation-defined whether the character `-` in the non-initial position in the scanset may be indicating a range, as in `[0-9]`. If width specifier is used, matches only up to _width_. Always stores a null character in addition to the characters matched (so the argument array must have room for at least _width+1_ characters).
 `d`   matches a **decimal integer**.  The format of the number is the same as expected by [`wcstol()`](../string/wide/wcstol) with the value `10` for the `base` argument.
`signed char*` or `unsigned char*`
`signed short*` or `unsigned short*`
`signed int*` or `unsigned int*`
`signed long*` or `unsigned long*`
`signed long long*` or `unsigned long long*`
[`intmax_t`](../types/integer)`*` or [`uintmax_t`](../types/integer)`*`

size_t*

ptrdiff_t*

N / A      i   匹配整數(shù)。數(shù)的格式是相同的通過按預(yù)期wcstol()與值0的base參數(shù)（基部由解析的第一字符確定）。

 `u`   matches an unsigned **decimal integer**.  The format of the number is the same as expected by [`wcstoul()`](../string/wide/wcstoul) with the value `10` for the `base` argument.
 `o`   matches an unsigned **octal integer**.  The format of the number is the same as expected by [`wcstoul()`](../string/wide/wcstoul) with the value `8` for the `base` argument.
 `x`, `X`   matches an unsigned **hexadecimal integer**.  The format of the number is the same as expected by [`wcstoul()`](../string/wide/wcstoul) with the value `16` for the `base` argument.
 `n`   returns the **number of characters read so far**.  No input is consumed. Does not increment the assignment count. If the specifier has assignment-suppressing operator defined, the behavior is undefined.
 `a`, `A`(C99)

e, E

f, F

g，G   匹配一個浮點數(shù)。數(shù)字的格式與預(yù)期的相同wcstof()。

N/A   N/A   float*

double*

N/A   N/A   N/A   N/A   long double*

 `p`   matches implementation defined character sequence defining a **pointer**.  `printf` family of functions should produce the same sequence using `%p` format specifier.

N/A   N/A   void**

n不適用不適用不適用不適用不適用不適用不適用不適用于任何指定字段寬度的最長輸入字符序列的   每個轉(zhuǎn)換說明符，或者正是轉(zhuǎn)換說明符所期望的或者是它期望的順序是從流中消耗的。在消耗序列之后的第一個字符（如果有的話）仍然未讀。如果消耗的序列長度為零或消費的序列不能如上所述進(jìn)行轉(zhuǎn)換，則會發(fā)生匹配失敗，除非文件結(jié)束，編碼錯誤或讀取錯誤阻止了來自流的輸入，在這種情況下，它是輸入失敗。

在嘗試解析輸入之前，除了[，，之外的所有轉(zhuǎn)換說明符都會消耗并放棄所有前導(dǎo)空白字符（如同通過調(diào)用一樣確定）。這些消耗的字符不會計入指定的最大字段寬度。cniswspace

如果l未使用長度說明符，則轉(zhuǎn)換說明符c，s并[執(zhí)行寬到多字節(jié)字符轉(zhuǎn)換，就像通過在第一個字符轉(zhuǎn)換之前使用初始化為零wcrtomb()的mbstate_t對象調(diào)用一樣。

除了匹配的字符之外，轉(zhuǎn)換說明符s并[始終存儲空終止符。目標(biāo)數(shù)組的大小必須至少比指定的字段寬度大1。在不指定目標(biāo)數(shù)組大小的情況下，使用%s或%[不安全gets。

對于固定寬度的整數(shù)類型（正確的轉(zhuǎn)換規(guī)格int8_t<inttypes.h>還（雖然，等等）都在頭定義SCNdMAX，SCNuMAX等是同義詞%jd，%ju等）。

每個轉(zhuǎn)換說明符的操作之后都有一個序列點; 這允許將多個字段存儲在相同的“匯”變量中。

在解析指數(shù)中不包含數(shù)字的不完整浮點值時（例如"100er"使用轉(zhuǎn)換說明符進(jìn)行解析），會消耗%f序列"100e"（可能有效的浮點數(shù)的最長前綴），從而導(dǎo)致匹配錯誤（消耗的序列不能轉(zhuǎn)換為浮點數(shù)），"r"剩余的?，F(xiàn)有的實現(xiàn)不遵循此規(guī)則并僅回滾消耗"100"，只留下"er"例如glibc錯誤1765。

 ...   -   receiving arguments

返回值

1-3）成功分配的接收參數(shù)數(shù)目，或者EOF在分配第一個接收參數(shù)前發(fā)生讀取失敗。

4-6) Same as (1-3), except that EOF is also returned if there is a runtime constraint violation.

例

參考

  • C11標(biāo)準(zhǔn)（ISO / IEC 9899：2011）：

    • 7.29.2.2 fwscanf功能（p：410-416）

    • 7.29.2.4 swscanf函數(shù)（p：417）

    • 7.29.2.12 wscanf函數(shù)（p：421）

    • K.3.9.1.2 fwscanf_s函數(shù)（p：628-629）

    • K.3.9.1.5 swscanf_s函數(shù)（p：631）

    • K.3.9.1.14 wscanf_s函數(shù)（p：638）

  • C99標(biāo)準(zhǔn)（ISO / IEC 9899：1999）：

    • 7.24.2.2 fwscanf函數(shù)（p：356-362）

    • 7.24.2.4 swscanf函數(shù)（p：362）

    • 7.24.2.12 wscanf函數(shù)（p：366-367）

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