NAME¶

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¶

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