How to achieve strncpy() functionality with strncpy_s() function?

Question

There\'re certain cases when I really need strncpy() funcitonalty - for example I have a function in a predefined interface that is passed an address of the buf

Answer 1

You might use memcpy_s instead.

HRESULT someFunction( char* buffer, size_t length )
{
    const char* toCopy = ...
    size_t actualLength = strlen( toCopy );
    if( actualLength > length ) {
        return E_UNEXPECTED; // doesn't fit, can't do anything reasonable 
    }
    else if ( actualLength < length ) {
        actualLength++; // copy null terminator too
    }
    memcpy_s( buffer, length, toCopy, actualLength );
    return S_OK;
}