iswcntrl
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   Defined in header  <wctype.h>
  | 
||
|   int iswcntrl( wint_t ch );  | 
(since C95) | |
Checks if the given wide character is a control character, i.e. codes 0x00-0x1F and 0x7F and any control characters specific to the current locale.
Parameters
| ch | - | wide character | 
Return value
Non-zero value if the wide character is a control character, zero otherwise.
Notes
ISO 30112 defines POSIX control characters as Unicode characters U+0000..U+001F, U+007F..U+009F, U+2028, and U+2029 (Unicode classes Cc, Zl, and Zp)
Example
Run this code
#include <locale.h> #include <stdio.h> #include <wchar.h> #include <wctype.h> int main(void) { wchar_t c = L'\u2028'; // the Unicode character "line separator" printf("In the default locale, iswcntrl(%#x) = %d\n", c, !!iswcntrl(c)); setlocale(LC_ALL, "en_US.utf8"); printf("In Unicode locale, iswcntrl(%#x) = %d\n", c, !!iswcntrl(c)); }
Output:
In the default locale, iswcntrl(0x2028) = 0 In Unicode locale, iswcntrl(0x2028) = 1
References
- C23 standard (ISO/IEC 9899:2024):
 
- 7.30.2.1.4 The iswcntrl function (p: TBD)
 
- C17 standard (ISO/IEC 9899:2018):
 
- 7.30.2.1.4 The iswcntrl function (p: TBD)
 
- C11 standard (ISO/IEC 9899:2011):
 
- 7.30.2.1.4 The iswcntrl function (p: 449)
 
- C99 standard (ISO/IEC 9899:1999):
 
- 7.25.2.1.4 The iswcntrl function (p: 395)
 
See also
|    checks if a character is a control character  (function)  | |
|   C++ documentation for iswcntrl 
 | |
| ASCII values | characters | 
 iscntrl  | 
|||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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
 |