std::wmemchr (3) Linux Manual Page

std::wmemchr – std::wmemchr

Synopsis

Defined in header<cwchar>

    const wchar_t *wmemchr(const wchar_t *ptr, wchar_t ch, std::size_t count);

wchar_t *wmemchr(wchar_t *ptr, wchar_t ch, std::size_t count);

Locates the first occurrence of wide character ch in the initial count wide characters of the wide character array pointed to by ptr.
If count is zero, the function returns a null pointer.

Parameters

ptr – pointer to the wide character array to be examined
ch – wide character to search for
count – number of wide characters to examine

Return value

Pointer to the location of the wide character, or a null pointer if no such character is found.

Example

// Run this code

#include <iostream>

#include <cwchar>

#include <clocale>

#include <locale>
int main()

{
    const wchar_t str[] = L"诺不轻信，故人不负我\0诺不轻许，故我不负人。";
    wchar_t target = L'许';
    const std::size_t sz = sizeof str / sizeof *str;
    if (const wchar_t *result = std::wmemchr(str, target, sz)) {
        std::setlocale(LC_ALL, "en_US.utf8");
        std::wcout.imbue(std::locale("en_US.utf8"));
        std::wcout << "Found '" << target
                   << "' at position " << result - str << "\n";
    }
}

Possible output:

  Found ‘许’ at position 14

See also

            searches an array for the first occurrence of a character
memchr (function)
            finds the first occurrence of a character
strchr (function)
            finds the first occurrence of a wide character in a wide string
wcschr (function)
find
find_if
find_if_not finds the first element satisfying specific criteria
            (function template)
(C++11)