std::iswcntrl(3)

NAME
std::iswcntrl - std::iswcntrl

Synopsis
   Defined in header <cwctype>
   int iswcntrl( std::wint_t ch );
   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.
   If the value of ch is neither representable as a wchar_t nor equal to the value of
   the macro WEOF, the behavior is undefined.

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 <clocale>
 #include <cwctype>
 #include <iostream>
 int main()
 {
     wchar_t c = L'\u2028'; // the Unicode character "line separator"
     std::cout << std::hex << std::showbase << std::boolalpha;
     std::cout << "in the default locale, iswcntrl(" << (std::wint_t)c << ") = "
               << (bool)std::iswcntrl(c) << '\n';
     std::setlocale(LC_ALL, "en_US.utf8");
     std::cout << "in Unicode locale, iswcntrl(" << (std::wint_t)c << ") = "
               << (bool)std::iswcntrl(c) << '\n';
 }

Output:
 in the default locale, iswcntrl(0x2028) = false
 in Unicode locale, iswcntrl(0x2028) = true

See also
                        checks if a character is classified as a control character by a
   iscntrl(std::locale) locale
                        (function template)
   iscntrl checks if a character is a control character
                        (function)
   C documentation for
   iswcntrl
        ASCII values characters iscntrl isprint isspace isblank isgraph ispunct isalnum isalpha isupper islower isdigit isxdigit decimal hexadecimal octal iswcntrl iswprint iswspace iswblank iswgraph iswpunct iswalnum iswalpha iswupper iswlower iswdigit iswxdigit 0–8 \x0–\x8 \0–\10 control codes ≠0 0 0 0 0 0 0 0 0 0 0 0
                        (NUL, etc.) 9 \x9 \11 tab (\t) ≠0 0 ≠0 ≠0 0 0 0 0 0 0 0 0
                        whitespaces 10–13 \xA–\xD \12–\15 (\n, \v, \f, ≠0 0 ≠0 0 0 0 0 0 0 0 0 0
                        \r) 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 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 0
                        QRSTUVWXYZ 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 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 0
                        qrstuvwxyz 123–126 \x7B–\x7E \172–\176 {|}~ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0 127 \x7F \177 backspace ≠0 0 0 0 0 0 0 0 0 0 0 0
                        character (DEL)