iswupper

 

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Null-terminated wide strings

Functions
Character manipulation
iswalnum (C95) iswalpha (C95) iswlower (C95) iswupper (C95) iswdigit (C95) iswxdigit (C95) iswblank (C99) wctype (C95) iswctype (C95)	iswcntrl (C95) iswgraph (C95) iswspace (C95) iswprint (C95) iswpunct (C95) towlower (C95) towupper (C95) wctrans (C95) towctrans (C95)
Conversions to numeric formats
wcstolwcstoll (C95)(C99) wcstoulwcstoull (C95)(C99)	wcstofwcstodwcstold (C99)(C95)(C99) wcstoimaxwcstoumax (C99)(C99)
String manipulation
wcslenwcsnlen_s (C95)(C11) wcscpywcscpy_s (C95)(C11) wcsncpywcsncpy_s (C95)(C11) wcscatwcscat_s (C95)(C11) wcsncatwcsncat_s (C95)(C11) wcsstr (C95)	wcscmp (C95) wcsncmp (C95) wcscoll (C95) wcsxfrm (C95) wcschr (C95) wcsrchr (C95) wcspbrk (C95) wcsspn (C95) wcscspn (C95) wcstokwcstok_s (C95)(C11)
Array manipulation
wmemcpywmemcpy_s (C95)(C11) wmemmovewmemmove_s (C95)(C11)	wmemcmp (C95) wmemchr (C95) wmemset (C95)

 

Defined in header <wctype.h>
int iswupper( wint_t ch );		(since C95)

Checks if the given wide character is an uppercase letter, i.e. one of ABCDEFGHIJKLMNOPQRSTUVWXYZ or any uppercase letter specific to the current locale.

Parameters

ch

-

wide character

Return value

Non-zero value if the wide character is an uppercase letter, zero otherwise.

Notes

ISO 30112 specifies which Unicode characters are include in POSIX upper category.

Example

Run this code

#include <locale.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>
 
int main(void)
{
    wchar_t c = L'\u053d'; // Armenian capital letter xeh ('Խ')
    printf("In the default locale, iswupper(%#x) = %d\n", c, !!iswupper(c));
    setlocale(LC_ALL, "en_US.utf8");
    printf("In Unicode locale, iswupper(%#x) = %d\n", c, !!iswupper(c));
}

Output:

In the default locale, iswupper(0x53d) = 0
In Unicode locale, iswupper(0x53d) = 1

References

• C23 standard (ISO/IEC 9899:2024):

• 7.30.2.1.11 The iswupper function (p: TBD)

• C17 standard (ISO/IEC 9899:2018):

• 7.30.2.1.11 The iswupper function (p: TBD)

• C11 standard (ISO/IEC 9899:2011):

• 7.30.2.1.11 The iswupper function (p: 451)

• C99 standard (ISO/IEC 9899:1999):

• 7.25.2.1.11 The iswupper function (p: 397)

See also

isupper	checks if a character is an uppercase character (function)
C++ documentation for iswupper

ASCII values			characters	iscntrl iswcntrl	isprint iswprint	isspace iswspace	isblank iswblank	isgraph iswgraph	ispunct iswpunct	isalnum iswalnum	isalpha iswalpha	isupper iswupper	islower iswlower	isdigit iswdigit	isxdigit iswxdigit
decimal	hexadecimal	octal
0–8	\x0–\x8	\0–\10	control codes (NUL, etc.)	≠0	0	0	0	0	0	0	0	0	0	0	0
9	\x9	\11	tab (\t)	≠0	0	≠0	≠0	0	0	0	0	0	0	0	0
10–13	\xA–\xD	\12–\15	whitespaces (\n, \v, \f, \r)	≠0	0	≠0	0	0	0	0	0	0	0	0	0
14–31	\xE–\x1F	\16–\37	control codes	≠0	0	0	0	0	0	0	0	0	0	0	0
32	\x20	\40	space	0	≠0	≠0	≠0	0	0	0	0	0	0	0	0
33–47	\x21–\x2F	\41–\57	!"#$%&'()*+,-./	0	≠0	0	0	≠0	≠0	0	0	0	0	0	0
48–57	\x30–\x39	\60–\71	0123456789	0	≠0	0	0	≠0	0	≠0	0	0	0	≠0	≠0
58–64	\x3A–\x40	\72–\100	:;<=>?@	0	≠0	0	0	≠0	≠0	0	0	0	0	0	0
65–70	\x41–\x46	\101–\106	ABCDEF	0	≠0	0	0	≠0	0	≠0	≠0	≠0	0	0	≠0
71–90	\x47–\x5A	\107–\132	GHIJKLMNOP QRSTUVWXYZ	0	≠0	0	0	≠0	0	≠0	≠0	≠0	0	0	0
91–96	\x5B–\x60	\133–\140	[\]^_`	0	≠0	0	0	≠0	≠0	0	0	0	0	0	0
97–102	\x61–\x66	\141–\146	abcdef	0	≠0	0	0	≠0	0	≠0	≠0	0	≠0	0	≠0
103–122	\x67–\x7A	\147–\172	ghijklmnop qrstuvwxyz	0	≠0	0	0	≠0	0	≠0	≠0	0	≠0	0	0
123–126	\x7B–\x7E	\173–\176	{|}~	0	≠0	0	0	≠0	≠0	0	0	0	0	0	0
127	\x7F	\177	backspace character (DEL)	≠0	0	0	0	0	0	0	0	0	0	0	0