std::iswcntrl

Header: <cwctype>

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.

# Declarations

int iswcntrl( std::wint_t ch );

# 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

#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';
}