iswblank
From cppreference.com
| Defined in header <wctype.h>
|
||
| int iswblank( wint_t ch ); |
(since C99) | |
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
- C23 standard (ISO/IEC 9899:2024):
- 7.30.2.1.3 The iswblank function (p: TBD)
- C17 standard (ISO/IEC 9899:2018):
- 7.30.2.1.3 The iswblank function (p: TBD)
- C11 standard (ISO/IEC 9899:2011):
- 7.30.2.1.3 The iswblank function (p: 449)
- C99 standard (ISO/IEC 9899:1999):
- 7.25.2.1.3 The iswblank function (p: 395)
See also
| (C99) |
checks if a character is a blank character (function) |
| C++ documentation for iswblank
| |
| ASCII values | characters |
isblank |
|||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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
|
GHIJKLMNOPQRSTUVWXYZ
|
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
|
ghijklmnopqrstuvwxyz
|
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
|