< cpp‎ | string‎ | multibyte
Defined in header <cwchar>
int wctob( std::wint_t c );

Narrows a wide character c if its multibyte character equivalent in the initial shift state is a single byte.

This is typically possible for the characters from the ASCII character set, since most multibyte encodings (such as UTF-8) use single bytes to encode those characters.


[edit] Parameters

c - wide character to narrow

[edit] Return value

EOF if c does not represent a multibyte character with length 1 in initial shift state.

Otherwise, the single-byte representation of c as unsigned char converted to int

[edit] Example

#include <clocale>
#include <cwchar>
#include <iostream>
void try_narrowing(wchar_t c)
    int cn = std::wctob(c);
    if(cn != EOF)
        std::cout << '\'' << c << "' narrowed to " << +cn << '\n';
        std::cout << '\'' << c << "' could not be narrowed\n";
int main()
    std::setlocale(LC_ALL, "th_TH.utf8");
    std::cout << std::hex << std::showbase << "In Thai UTF-8 locale:\n";
    std::setlocale(LC_ALL, "th_TH.tis620");
    std::cout << "In Thai TIS-620 locale:\n";


In Thai UTF-8 locale:
'0x61' narrowed to 0x61
'0xe5b' could not be narrowed
In Thai TIS-620 locale:
'0x61' narrowed to 0x61
'0xe5b' narrowed to 0xfb

[edit] See also

widens a single-byte narrow character to wide character, if possible
narrows characters
(public member function of std::basic_ios)
invokes do_narrow
(public member function of std::ctype)
C documentation for wctob