Synopsis
wchar_t *wcsncpy(wchar_t *s1,
                 const wchar_t *s2,
                 size_t n);
Description

wcsncpy copies not more than n wide characters from the array pointed to by s2 to the array pointed to by s1. Wide characters that follow a null wide character in s2 are not copied. The behavior of wcsncpy is undefined if copying takes place between objects that overlap. If the array pointed to by s2 is a wide string that is shorter than n wide characters, null wide characters are appended to the copy in the array pointed to by s1, until n characters in all have been written.

wcsncpy returns the value of s1.