1#include <wchar.h>23#undef wcsncpy45wchar_t *6wcsncpy(wchar_t *restrict s1, const wchar_t *restrict s2, size_t n)7{8 wchar_t *ret = s1;910 for (; n > 0 && *s2; --n)11 *s1++ = *s2++;1213 while (n-- > 0)14 *s1++ = '\0';1516 return ret;1718}