Standard library header <cwchar>
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This header was originally in the C standard library as <wchar.h>.
This header is part of the null-terminated wide and multibyte strings libraries. It also provides some C-style I/O functions and conversion from C-style Date.
Contents
[edit] Macros
WEOF
std::wint_t
used to indicate errors (macro constant)
WCHAR_MIN
(macro constant)
WCHAR_MAX
(macro constant)
[edit] Types
wint_t
integer type that can hold any valid wide character and at least one more value
[edit] Functions
String manipulation
String examination
returns the length of the maximum initial segment that consists
of only the wide characters found in another wide string
(function) [edit]
of only the wide characters found in another wide string
(function) [edit]
returns the length of the maximum initial segment that consists
of only the wide not found in another wide string
(function) [edit]
of only the wide not found in another wide string
(function) [edit]
finds the first location of any wide character in one wide string, in another wide string
(function) [edit]
(function) [edit]
Wide character array manipulation
copies a certain amount of wide characters between two, possibly overlapping, arrays
(function) [edit]
(function) [edit]
Multibyte/wide character conversion
Input/Output
(C++11)(C++11)(C++11)
or a buffer using variable argument list
(function) [edit]
prints formatted wide character output to stdout , a file stream
or a buffer using variable argument list
(function) [edit]
or a buffer using variable argument list
(function) [edit]
String conversions
[edit] Notes
- NULL is also defined in the following headers:
- std::size_t is also defined in the following headers:
-
std::wint_t
is also defined in the following headers: - std::tm is also defined in the following headers:
[edit] Synopsis
namespace std { using size_t = /* see description */; // freestanding using mbstate_t = /* see description */; // freestanding using wint_t = /* see description */; // freestanding struct tm; int fwprintf(FILE* stream, const wchar_t* format, ...); int fwscanf(FILE* stream, const wchar_t* format, ...); int swprintf(wchar_t* s, size_t n, const wchar_t* format, ...); int swscanf(const wchar_t* s, const wchar_t* format, ...); int vfwprintf(FILE* stream, const wchar_t* format, va_list arg); int vfwscanf(FILE* stream, const wchar_t* format, va_list arg); int vswprintf(wchar_t* s, size_t n, const wchar_t* format, va_list arg); int vswscanf(const wchar_t* s, const wchar_t* format, va_list arg); int vwprintf(const wchar_t* format, va_list arg); int vwscanf(const wchar_t* format, va_list arg); int wprintf(const wchar_t* format, ...); int wscanf(const wchar_t* format, ...); wint_t fgetwc(FILE* stream); wchar_t* fgetws(wchar_t* s, int n, FILE* stream); wint_t fputwc(wchar_t c, FILE* stream); int fputws(const wchar_t* s, FILE* stream); int fwide(FILE* stream, int mode); wint_t getwc(FILE* stream); wint_t getwchar(); wint_t putwc(wchar_t c, FILE* stream); wint_t putwchar(wchar_t c); wint_t ungetwc(wint_t c, FILE* stream); double wcstod(const wchar_t* nptr, wchar_t** endptr); float wcstof(const wchar_t* nptr, wchar_t** endptr); long double wcstold(const wchar_t* nptr, wchar_t** endptr); long int wcstol(const wchar_t* nptr, wchar_t** endptr, int base); long long int wcstoll(const wchar_t* nptr, wchar_t** endptr, int base); unsigned long int wcstoul(const wchar_t* nptr, wchar_t** endptr, int base); unsigned long long int wcstoull(const wchar_t* nptr, wchar_t** endptr, int base); wchar_t* wcscpy(wchar_t* s1, const wchar_t* s2); // freestanding wchar_t* wcsncpy(wchar_t* s1, const wchar_t* s2, size_t n); // freestanding wchar_t* wmemcpy(wchar_t* s1, const wchar_t* s2, size_t n); // freestanding wchar_t* wmemmove(wchar_t* s1, const wchar_t* s2, size_t n); // freestanding wchar_t* wcscat(wchar_t* s1, const wchar_t* s2); // freestanding wchar_t* wcsncat(wchar_t* s1, const wchar_t* s2, size_t n); // freestanding int wcscmp(const wchar_t* s1, const wchar_t* s2); // freestanding int wcscoll(const wchar_t* s1, const wchar_t* s2); int wcsncmp(const wchar_t* s1, const wchar_t* s2, size_t n); // freestanding size_t wcsxfrm(wchar_t* s1, const wchar_t* s2, size_t n); int wmemcmp(const wchar_t* s1, const wchar_t* s2, size_t n); // freestanding const wchar_t* wcschr(const wchar_t* s, wchar_t c); // freestanding wchar_t* wcschr(wchar_t* s, wchar_t c); // freestanding size_t wcscspn(const wchar_t* s1, const wchar_t* s2); // freestanding const wchar_t* wcspbrk(const wchar_t* s1, const wchar_t* s2); // freestanding wchar_t* wcspbrk(wchar_t* s1, const wchar_t* s2); // freestanding const wchar_t* wcsrchr(const wchar_t* s, wchar_t c); // freestanding wchar_t* wcsrchr(wchar_t* s, wchar_t c); // freestanding size_t wcsspn(const wchar_t* s1, const wchar_t* s2); // freestanding const wchar_t* wcsstr(const wchar_t* s1, const wchar_t* s2); // freestanding wchar_t* wcsstr(wchar_t* s1, const wchar_t* s2); // freestanding wchar_t* wcstok(wchar_t* s1, const wchar_t* s2, wchar_t** ptr); // freestanding const wchar_t* wmemchr(const wchar_t* s, wchar_t c, size_t n); // freestanding wchar_t* wmemchr(wchar_t* s, wchar_t c, size_t n); // freestanding size_t wcslen(const wchar_t* s); // freestanding wchar_t* wmemset(wchar_t* s, wchar_t c, size_t n); // freestanding size_t wcsftime(wchar_t* s, size_t maxsize, const wchar_t* format, const tm* timeptr); wint_t btowc(int c); int wctob(wint_t c); // multibyte / wide string and character conversion functions int mbsinit(const mbstate_t* ps); size_t mbrlen(const char* s, size_t n, mbstate_t* ps); size_t mbrtowc(wchar_t* pwc, const char* s, size_t n, mbstate_t* ps); size_t wcrtomb(char* s, wchar_t wc, mbstate_t* ps); size_t mbsrtowcs(wchar_t* dst, const char** src, size_t len, mbstate_t* ps); size_t wcsrtombs(char* dst, const wchar_t** src, size_t len, mbstate_t* ps); } #define NULL /* see description */ // freestanding #define WCHAR_MAX /* see description */ // freestanding #define WCHAR_MIN /* see description */ // freestanding #define WEOF /* see description */ // 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 345 | C++98 | std::tm was not provided in <cwchar>
|
provided |