UniStrncpy copies not more than n code elements (code elements that follow a null code element are not copied) from the code element array pointed to by ucs2 to the code element array pointed to by ucs1. If copying takes place between objects that overlap, the results are unpredictable. If the code element array pointed to by ucs2 is a code element string that is shorter than n code elements, null code elements are appended to the copy in the code element array pointed to by ucs1, until n code elements, in all, have been written.