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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(chǔ)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(gè)期望兩個(gè)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(shí)成一個(gè)單一的寬字符),除了在運(yùn)行時(shí)檢測(cè)到以下錯(cuò)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(huì)超過為每個(gè)轉(zhuǎn)換說明符提供的第二個(gè)(rsize_t)參數(shù)所寫的字符數(shù)
可選地,還有任何其他可檢測(cè)到的錯(cuò)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(shí)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>
。
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 | - | 指向一個(gè)以null結(jié)束的寬字符串的指針,指定如何讀取輸入。格式字符串由非空白寬字符(除%外)組成:格式字符串中的每個(gè)這樣的字符只消耗輸入流中的一個(gè)完全相同的字符,或者如果流中的下一個(gè)字符不相等,則會(huì)導(dǎo)致函數(shù)失敗。空格字符:格式字符串中的任何單個(gè)空格字符都會(huì)消耗輸入中所有可用的連續(xù)空格字符(如同通過在循環(huán)中調(diào)用iswspace一樣確定)。請(qǐng)注意,格式字符串中的“\ n”,“”,“\ t \ t”或其他空格沒有區(qū)別。轉(zhuǎn)換規(guī)格。每個(gè)轉(zhuǎn)換規(guī)范具有以下格式:介紹%字符(可選)分配抑制字符*。如果存在此選項(xiàng),則函數(shù)不會(huì)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)行當(dāng)前轉(zhuǎn)換規(guī)范指定的轉(zhuǎn)換時(shí)允許使用的最大字符數(shù)。請(qǐng)注意,如果未提供寬度,%s和%[可能會(huì)導(dǎo)致緩沖區(qū)溢出。(可選)長(zhǎng)度修飾符,用于指定接收參數(shù)的大小,即實(shí)際的目標(biāo)類型。這會(huì)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(qǐng)參閱下表)。轉(zhuǎn)換格式說明符以下格式說明符可用:轉(zhuǎn)換說明符說明參數(shù)類型長(zhǎng)度修飾符hh(C99)。h(無)ll(C99)。j(C99)。z(C99)。t(C99)。L%匹配字面值%N / AN / AN / AN / AN / AN / AN / AN / AN /與c匹配的字符或字符序列如果使用寬度說明符,則匹配寬度寬的字符(參數(shù)必須是指向具有足夠空間的陣列的指針)。與%s和%[不同,不會(huì)將空字符追加到數(shù)組。N / AN / A char * wchar_t * N / AN / AN / AN / AN / A與非空白字符序列(字符串)匹配如果使用寬度說明符,則匹配寬度或直到第一個(gè)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(chǔ)一個(gè)空字符(所以參數(shù)數(shù)組必須至少有寬度+ 1個(gè)字符的空間)。集匹配字符集中的非空字符序列。如果該集合的第一個(gè)字符是^,則不匹配該集合中的所有字符。如果該集合以]或^]開頭,則該字符也包含在集合中。它是實(shí)現(xiàn)定義的,字符 - 在掃描集中的非初始位置可以指示一個(gè)范圍,如0-9。如果使用寬度說明符,則只匹配寬度。除了匹配的字符外,總是存儲(chǔ)一個(gè)空字符(所以參數(shù)數(shù)組必須至少有寬度+ 1個(gè)字符的空間)。d匹配一個(gè)十進(jìn)制整數(shù)。數(shù)字的格式與wcstol()預(yù)期的基本參數(shù)為10的值相同。有符號(hào)字符*或無符號(hào)字符*有符號(hào)短符號(hào)*或無符號(hào)短符號(hào)*有符號(hào)整數(shù)*或無符號(hào)整數(shù)*有符號(hào)長(zhǎng)符號(hào)*無符號(hào)長(zhǎng)符號(hào)*長(zhǎng)符號(hào)*長(zhǎng)符號(hào)或無符號(hào)長(zhǎng)符號(hào)* intmax_t *或uintmax_t * size_t * ptrdiff_t * N / A i匹配一個(gè)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(gè)字符決定)。你匹配一個(gè)無符號(hào)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。o匹配一個(gè)無符號(hào)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(gè)無符號(hào)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。n返回到目前為止讀取的字符數(shù)。沒有輸入被消耗。不增加分配計(jì)數(shù)。如果說明符具有定義的分配抑制運(yùn)算符,則行為是未定義的。a,A(C99)e,E f,F(xiàn) g,G匹配一個(gè)浮點(diǎn)數(shù)。數(shù)字的格式與wcstof()的預(yù)期相同。N / AN / A float * double * N / AN / AN / AN / long long double * p匹配定義指針的實(shí)現(xiàn)定義字符序列。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 / AN / A void ** N / AN / AN / AN / AN / AN / A對(duì)于除n以外的每個(gè)轉(zhuǎn)換說明符,輸入字符的最長(zhǎng)序列不超過任何指定的字段寬度,并且或者正是轉(zhuǎn)換說明符所期望的或者是期望的序列的前綴,是從流中消耗的東西。在消耗序列之后的第一個(gè)字符(如果有的話)仍然未讀。如果消耗的序列長(zhǎng)度為零或消費(fèi)的序列無法如上所述進(jìn)行轉(zhuǎn)換,則會(huì)發(fā)生匹配失敗,除非文件結(jié)束,編碼錯(cuò)誤或讀取錯(cuò)誤阻止來自流的輸入,在這種情況下,它是輸入失敗。在嘗試解析輸入之前,除[,c和n之外的所有轉(zhuǎn)換說明符都會(huì)消耗并放棄所有前導(dǎo)空白字符(如同調(diào)用iswspace一樣確定)。這些消耗的字符不會(huì)計(jì)入指定的最大字段寬度。如果未使用長(zhǎng)度說明符l,則轉(zhuǎn)換說明符c,s和[執(zhí)行寬到多字節(jié)字符轉(zhuǎn)換,就像調(diào)用wcrtomb()時(shí)mbstate_t對(duì)象在第一個(gè)字符轉(zhuǎn)換之前已初始化為零一樣。轉(zhuǎn)換說明符s和[除了匹配的字符外,總是存儲(chǔ)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。使用%s或%[,不指定目標(biāo)數(shù)組大小,與get一樣不安全。固定寬度整數(shù)類型(int8_t等)的正確轉(zhuǎn)換規(guī)范在標(biāo)頭<inttypes.h>中定義(盡管SCNdMAX,SCNuMAX等與%jd,%ju等同義)。每個(gè)轉(zhuǎn)換說明符的操作之后都有一個(gè)序列點(diǎn); 這允許將多個(gè)字段存儲(chǔ)在相同的“ 導(dǎo)致匹配錯(cuò)誤(消耗的序列不能轉(zhuǎn)換為浮點(diǎn)數(shù)),并保留“r”?,F(xiàn)有的實(shí)現(xiàn)不遵循這個(gè)規(guī)則,并回滾到只消耗“100”,留下“呃”,例如glibc錯(cuò)誤1765。導(dǎo)致匹配錯(cuò)誤(消耗的序列不能轉(zhuǎn)換為浮點(diǎn)數(shù)),并保留“r”?,F(xiàn)有的實(shí)現(xiàn)不遵循這個(gè)規(guī)則,并回滾到只消耗“100”,留下“呃”,例如glibc錯(cuò)誤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(gè)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(gè)字符決定)。 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
在 | 匹配一個(gè)無符號(hào)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(gè)無符號(hào)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(gè)無符號(hào)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(jì)數(shù)。如果說明符具有定義的分配抑制運(yùn)算符,則行為是未定義的。 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
a,A(C99)e,E f,F(xiàn) g,G | 匹配一個(gè)浮點(diǎn)數(shù)。數(shù)字的格式與wcstof()的預(yù)期相同。 | N / A | N / A | 浮動(dòng)* | 雙* | N / A | N / A | N / A | N / A | 長(zhǎng)雙* | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
p | 匹配定義指針的實(shí)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(gè)這樣的字符都只消耗輸入流中的一個(gè)完全相同的字符,或者如果流中的下一個(gè)字符不相等,則會(huì)導(dǎo)致函數(shù)失敗。
空白字符:格式字符串中的任何單個(gè)空白字符都會(huì)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(qǐng)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(gè)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(xiàng),則函數(shù)不會(huì)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(shí)允許使用的最大字符數(shù)。請(qǐng)注意,如果未提供寬度,%s和%[可能會(huì)導(dǎo)致緩沖區(qū)溢出。
(可選)長(zhǎng)度修飾符,用于指定接收參數(shù)的大小,即實(shí)際的目標(biāo)類型。這會(huì)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(qǐng)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(zhǎng)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(gè)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(gè)指向陣列有足夠的空間)。與%s和%[不同,不會(huì)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(gè)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(chǔ)一個(gè)空字符(所以參數(shù)數(shù)組必須至少有寬度+ 1個(gè)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(gè)浮點(diǎn)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(zhǎng)輸入字符序列的 每個(gè)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(gè)字符(如果有的話)仍然未讀。如果消耗的序列長(zhǎng)度為零或消費(fèi)的序列不能如上所述進(jìn)行轉(zhuǎn)換,則會(huì)發(fā)生匹配失敗,除非文件結(jié)束,編碼錯(cuò)誤或讀取錯(cuò)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(huì)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(huì)計(jì)入指定的最大字段寬度。cniswspace
如果l
未使用長(zhǎng)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(gè)字符轉(zhuǎn)換之前使用初始化為零wcrtomb()
的mbstate_t
對(duì)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(chǔ)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(duì)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(gè)轉(zhuǎn)換說明符的操作之后都有一個(gè)序列點(diǎn); 這允許將多個(gè)字段存儲(chǔ)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(diǎn)值時(shí)(例如"100er"
使用轉(zhuǎn)換說明符進(jìn)行解析),會(huì)消耗%f
序列"100e"
(可能有效的浮點(diǎn)數(shù)的最長(zhǎng)前綴),從而導(dǎo)致匹配錯(cuò)誤(消耗的序列不能轉(zhuǎn)換為浮點(diǎn)數(shù)),"r"
剩余的?,F(xiàn)有的實(shí)現(xiàn)不遵循此規(guī)則并僅回滾消耗"100"
,只留下"er"
例如glibc錯(cuò)誤1765。
... - receiving arguments
1-3)成功分配的接收參數(shù)數(shù)目,或者EOF
在分配第一個(gè)接收參數(shù)前發(fā)生讀取失敗。
4-6)與(1-3)相同,但是EOF
如果存在運(yùn)行時(shí)約束沖突,也會(huì)返回。
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)