wchar.h — wide-character handling
#include <wchar.h>
[CX] Some of the functionality described on this reference page extends the ISO C standard. Applications shall define the appropriate feature test macro (see XSH 2.2 The Compilation Environment) to enable the visibility of these symbols in this header.The <wchar.h> header shall define the following types:
- FILE
- [CX] As described in <stdio.h>.
- locale_t
- [CX] As described in <locale.h>.
- mbstate_t
- A complete object type other than an array type that can hold the conversion state information necessary to convert between sequences of (possibly multi-byte) characters and wide characters. [CX] If a codeset is being used such that an mbstate_t needs to preserve more than two levels of reserved state, the results are unspecified.
- size_t
- As described in <stddef.h>.
- va_list
- [CX] As described in <stdarg.h>.
- wchar_t
- As described in <stddef.h>.
- wint_t
- An integer type capable of storing any valid value of wchar_t or WEOF.
The tag tm shall be declared as naming an incomplete structure type, the contents of which are described in the <time.h> header.
The implementation shall support one or more programming environments in which the width of wint_t is no greater than the width of type long. The names of these programming environments can be obtained using the confstr() function or the getconf utility.
The <wchar.h> header shall define the following macros:
- WCHAR_MAX
- As described in <stdint.h>.
- WCHAR_MIN
- As described in <stdint.h>.
- WEOF
- Constant expression of type wint_t that is returned by several WP functions to indicate end-of-file.
- NULL
- As described in <stddef.h>.
[CX] Inclusion of the <wchar.h> header may make visible all symbols from the headers <ctype.h>, <string.h>, <stdarg.h>, <stddef.h>, <stdio.h>, <stdlib.h>, and <time.h>.
The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided for use with ISO C standard compilers. Arguments to functions in this list can point to arrays containing wchar_t values that do not correspond to members of the character set of the current locale. Such values shall be processed according to the specified semantics, unless otherwise stated.
wint_t btowc(int); wint_t fgetwc(FILE *); wchar_t *fgetws(wchar_t *restrict, int, FILE *restrict); wint_t fputwc(wchar_t, FILE *); int fputws(const wchar_t *restrict, FILE *restrict); int fwide(FILE *, int); int fwprintf(FILE *restrict, const wchar_t *restrict, ...); int fwscanf(FILE *restrict, const wchar_t *restrict, ...); wint_t getwc(FILE *); wint_t getwchar(void); size_t mbrlen(const char *restrict, size_t, mbstate_t *restrict); size_t mbrtowc(wchar_t *restrict, const char *restrict, size_t, mbstate_t *restrict); int mbsinit(const mbstate_t *); [CX] size_t mbsnrtowcs(wchar_t *restrict, const char **restrict, size_t, size_t, mbstate_t *restrict); size_t mbsrtowcs(wchar_t *restrict, const char **restrict, size_t, mbstate_t *restrict); [CX] FILE *open_wmemstream(wchar_t **, size_t *); wint_t putwc(wchar_t, FILE *); wint_t putwchar(wchar_t); int swprintf(wchar_t *restrict, size_t, const wchar_t *restrict, ...); int swscanf(const wchar_t *restrict, const wchar_t *restrict, ...); wint_t ungetwc(wint_t, FILE *); int vfwprintf(FILE *restrict, const wchar_t *restrict, va_list); int vfwscanf(FILE *restrict, const wchar_t *restrict, va_list); int vswprintf(wchar_t *restrict, size_t, const wchar_t *restrict, va_list); int vswscanf(const wchar_t *restrict, const wchar_t *restrict, va_list); int vwprintf(const wchar_t *restrict, va_list); int vwscanf(const wchar_t *restrict, va_list); [CX] wchar_t *wcpcpy(wchar_t *restrict, const wchar_t *restrict); wchar_t *wcpncpy(wchar_t *restrict, const wchar_t *restrict, size_t); size_t wcrtomb(char *restrict, wchar_t, mbstate_t *restrict); [CX] int wcscasecmp(const wchar_t *, const wchar_t *); int wcscasecmp_l(const wchar_t *, const wchar_t *, locale_t); wchar_t *wcscat(wchar_t *restrict, const wchar_t *restrict); wchar_t *wcschr(const wchar_t *, wchar_t); int wcscmp(const wchar_t *, const wchar_t *); int wcscoll(const wchar_t *, const wchar_t *); [CX] int wcscoll_l(const wchar_t *, const wchar_t *, locale_t); wchar_t *wcscpy(wchar_t *restrict, const wchar_t *restrict); size_t wcscspn(const wchar_t *, const wchar_t *); [CX] wchar_t *wcsdup(const wchar_t *); size_t wcsftime(wchar_t *restrict, size_t, const wchar_t *restrict, const struct tm *restrict); [CX] size_t wcslcat(wchar_t *restrict, const wchar_t *restrict, size_t); size_t wcslcpy(wchar_t *restrict, const wchar_t *restrict, size_t); size_t wcslen(const wchar_t *); [CX] int wcsncasecmp(const wchar_t *, const wchar_t *, size_t); int wcsncasecmp_l(const wchar_t *, const wchar_t *, size_t, locale_t); wchar_t *wcsncat(wchar_t *restrict, const wchar_t *restrict, size_t); int wcsncmp(const wchar_t *, const wchar_t *, size_t); wchar_t *wcsncpy(wchar_t *restrict, const wchar_t *restrict, size_t); [CX] size_t wcsnlen(const wchar_t *, size_t); size_t wcsnrtombs(char *restrict, const wchar_t **restrict, size_t, size_t, mbstate_t *restrict); wchar_t *wcspbrk(const wchar_t *, const wchar_t *); wchar_t *wcsrchr(const wchar_t *, wchar_t); size_t wcsrtombs(char *restrict, const wchar_t **restrict, size_t, mbstate_t *restrict); size_t wcsspn(const wchar_t *, const wchar_t *); wchar_t *wcsstr(const wchar_t *restrict, const wchar_t *restrict); double wcstod(const wchar_t *restrict, wchar_t **restrict); float wcstof(const wchar_t *restrict, wchar_t **restrict); wchar_t *wcstok(wchar_t *restrict, const wchar_t *restrict, wchar_t **restrict); long wcstol(const wchar_t *restrict, wchar_t **restrict, int); long double wcstold(const wchar_t *restrict, wchar_t **restrict); long long wcstoll(const wchar_t *restrict, wchar_t **restrict, int); unsigned long wcstoul(const wchar_t *restrict, wchar_t **restrict, int); unsigned long long wcstoull(const wchar_t *restrict, wchar_t **restrict, int); [XSI] int wcswidth(const wchar_t *, size_t); size_t wcsxfrm(wchar_t *restrict, const wchar_t *restrict, size_t); [CX] size_t wcsxfrm_l(wchar_t *restrict, const wchar_t *restrict, size_t, locale_t); int wctob(wint_t); [XSI] int wcwidth(wchar_t); wchar_t *wmemchr(const wchar_t *, wchar_t, size_t); int wmemcmp(const wchar_t *, const wchar_t *, size_t); wchar_t *wmemcpy(wchar_t *restrict, const wchar_t *restrict, size_t); wchar_t *wmemmove(wchar_t *, const wchar_t *, size_t); wchar_t *wmemset(wchar_t *, wchar_t, size_t); int wprintf(const wchar_t *restrict, ...); int wscanf(const wchar_t *restrict, ...);
None.
None.
None.
<ctype.h>, <locale.h> , <stdarg.h>, <stddef.h> , <stdint.h>, <stdio.h>, <stdlib.h>, <string.h>, <time.h>, <wctype.h>
XSH 2.2 The Compilation Environment, btowc, confstr, fgetwc, fgetws, fputwc, fputws, fwide, fwprintf, fwscanf, getwc, getwchar, iswalnum, iswalpha, iswcntrl, iswctype, iswdigit, iswgraph, iswlower, iswprint, iswpunct, iswspace, iswupper, iswxdigit, mbrlen, mbrtowc, mbsinit, mbsrtowcs, open_memstream, putwc, putwchar, towlower, towupper, ungetwc, vfwprintf, vfwscanf, wcrtomb, wcscasecmp, wcscat, wcschr, wcscmp, wcscoll, wcscpy, wcscspn, wcsdup, wcsftime, wcslcat, wcslen, wcsncat, wcsncmp, wcsncpy, wcspbrk, wcsrchr, wcsrtombs, wcsspn, wcsstr, wcstod, wcstok, wcstol, wcstoul, wcswidth, wcsxfrm, wctob, wctype, wcwidth, wmemchr, wmemcmp, wmemcpy, wmemmove, wmemset
XCU getconf
First released in Issue 4.
Aligned with the ISO/IEC 9899:1990/Amendment 1:1995 (E).
The Open Group Corrigendum U021/10 is applied. The prototypes for wcswidth() and wcwidth() are marked as extensions.
The Open Group Corrigendum U028/5 is applied, correcting the prototype for the mbsinit() function.
The following changes are made for alignment with the ISO/IEC 9899:1999 standard:
Various function prototypes are updated to add the restrict keyword.
The functions vfwscanf(), vswscanf(), wcstof(), wcstold(), wcstoll(), and wcstoull() are added.
The type wctype_t, the isw*(), to*(), and wctype() functions are marked as XSI extensions.
IEEE Std 1003.1-2001/Cor 1-2002, item XBD/TC1/D6/26 is applied, adding the APPLICATION USAGE section.
The mbsnrtowcs(), open_wmemstream(), wcpcpy(), wcpncpy(), wcscasecmp(), wcsdup(), wcsncasecmp(), wcsnlen(), and wcsnrtombs() functions are added from The Open Group Technical Standard, 2006, Extended API Set Part 1.
The wcscasecmp_l(), wcsncasecmp_l(), wcscoll_l(), and wcsxfrm_l() functions are added from The Open Group Technical Standard, 2006, Extended API Set Part 4.
The wctype_t type, and the isw*(), towlower(), and towupper() functions are marked obsolescent in <wchar.h> since the ISO C standard requires the declarations to be in <wctype.h>.
This reference page is clarified with respect to macros and symbolic constants, and a declaration for the locale_t type is added.
POSIX.1-2008, Technical Corrigendum 1, XBD/TC1-2008/0081 [380] is applied.
POSIX.1-2008, Technical Corrigendum 2, XBD/TC2-2008/0088 [73] is applied.
Austin Group Defect 986 is applied, adding wcslcat() and wcslcpy().
Austin Group Defect 1302 is applied, aligning this header with the ISO/IEC 9899:2018 standard.
Austin Group Defect 1330 is applied, removing obsolescent interfaces.
Austin Group Defect 1352 is applied, changing the APPLICATION USAGE and RATIONALE sections.
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