# std::wmemcpy

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< cpp‎ | string‎ | wide

Defined in header `<cwchar>` |  |
wchar_t* wmemcpy( wchar_t* dest, const wchar_t* src, std::size_t count ); |  |

Copies exactly count successive wide characters from the wide character array pointed to by src to the wide character array pointed to by dest. If the objects overlap, the behavior is undefined. If count is zero, the function does nothing.

### Parameters

dest | - | pointer to the wide character array to copy to
src | - | pointer to the wide character array to copy from
count | - | number of wide characters to copy

### Return value

dest

### Notes

This function's analog for byte strings is std::strncpy, not std::strcpy.

This function is not locale-sensitive and pays no attention to the values of the wchar_t objects it copies: nulls as well as invalid characters are copied too.

### Example

Run this code

    #include <clocale>
    #include <cwchar>
    #include <iostream>
    #include <iterator>
    #include <locale>

    int main(void)
    {
        const wchar_t from1[] = L"नमस्ते";
        const wchar_t from2[] = L"Բարև";
        const std::size_t sz1 = std::size(from1);
        const std::size_t sz2 = std::size(from2);
        wchar_t to[sz1 + sz2];

        std::wmemcpy(to, from1, sz1); // copy from1, along with its null terminator
        std::wmemcpy(to + sz1, from2, sz2); // append from2, along with its null terminator

        std::setlocale(LC_ALL, "en_US.utf8");
        std::wcout.imbue(std::locale("en_US.utf8"));
        std::wcout << L"Wide array contains: ";
        for (std::size_t n = 0; n < std::size(to); ++n)
            if (to[n])
                std::wcout << to[n];
            else
                std::wcout << L"\\0";
        std::wcout << L'\n';
    }

Possible output:

    Wide array contains: नमस्ते\0Բարև\0

### See also

strncpy | copies a certain amount of characters from one string to another (function)
wmemmove | copies a certain amount of wide characters between two, possibly overlapping, arrays (function)

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