iswblank

 

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Technical Specifications

Symbol index

 

Strings library

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Null-terminated wide strings

Functions
Character manipulation
iswalnum (哋它亢95) iswalpha (哋它亢95) iswlower (哋它亢95) iswupper (哋它亢95) iswdigit (哋它亢95) iswxdigit (哋它亢95) iswblank (哋它亢99) wctype (哋它亢95) iswctype (哋它亢95)	iswcntrl (哋它亢95) iswgraph (哋它亢95) iswspace (哋它亢95) iswprint (哋它亢95) iswpunct (哋它亢95) towlower (哋它亢95) towupper (哋它亢95) wctrans (哋它亢95) towctrans (哋它亢95)
Conversions to numeric formats
wcstolwcstoll (哋它亢95)(哋它亢99) wcstoulwcstoull (哋它亢95)(哋它亢99)	wcstofwcstodwcstold (哋它亢99)(哋它亢95)(哋它亢99) wcstoimaxwcstoumax (哋它亢99)(哋它亢99)
String manipulation
wcslenwcsnlen_s (哋它亢95)(哋它亢11) wcscpywcscpy_s (哋它亢95)(哋它亢11) wcsncpywcsncpy_s (哋它亢95)(哋它亢11) wcscatwcscat_s (哋它亢95)(哋它亢11) wcsncatwcsncat_s (哋它亢95)(哋它亢11) wcsstr (哋它亢95)	wcscmp (哋它亢95) wcsncmp (哋它亢95) wcscoll (哋它亢95) wcsxfrm (哋它亢95) wcschr (哋它亢95) wcsrchr (哋它亢95) wcspbrk (哋它亢95) wcsspn (哋它亢95) wcscspn (哋它亢95) wcstokwcstok_s (哋它亢95)(哋它亢11)
Array manipulation
wmemcpywmemcpy_s (哋它亢95)(哋它亢11) wmemmovewmemmove_s (哋它亢95)(哋它亢11)	wmemcmp (哋它亢95) wmemchr (哋它亢95) wmemset (哋它亢95)

 

Defined in header <wctype.h>
int iswblank( wint_t ch );		(since 哋它亢99)

Checks if the given wide character is classified as blank character (that is, a whitespace character used to separate words in a sentence) by the current C locale. In the default C locale, only space (0x20) and horizontal tab (0x09) are blank characters.

Parameters

ch

-

wide character

Return value

Non-zero value if the wide character is a blank character, zero otherwise.

Notes

ISO 30112 defines POSIX blank characters as Unicode characters U+0009, U+0020, U+1680, U+180E, U+2000..U+2006, U+2008, U+200A, U+205F, and U+3000.

Example

Run this code

#include <locale.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>
 
int main(void)
{
    wchar_t c = L'\u3000'; // Ideographic space ('　')
    printf("In the default locale, iswblank(%#x) = %d\n", c, !!iswblank(c));
    setlocale(LC_ALL, "en_US.utf8");
    printf("In Unicode locale, iswblank(%#x) = %d\n", c, !!iswblank(c));
}

Output:

In the default locale, iswblank(0x3000) = 0
In Unicode locale, iswblank(0x3000) = 1

References

• 哋它亢23 standard (ISO/IEC 9899:2023):

• 7.30.2.1.3 The iswblank function (p: TBD)

• 哋它亢17 standard (ISO/IEC 9899:2018):

• 7.30.2.1.3 The iswblank function (p: TBD)

• 哋它亢11 standard (ISO/IEC 9899:2011):

• 7.30.2.1.3 The iswblank function (p: 449)

• 哋它亢99 standard (ISO/IEC 9899:1999):

• 7.25.2.1.3 The iswblank function (p: 395)

See also

isblank (哋它亢99)

checks if a character is a blank character (function)

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	\172–\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