wcpcpy is the wide-character equivalent of stpcpy. It copies the wide character string src, including the terminating L'\0' character, to the array dest.
The strings may not overlap.
The programmer must ensure that there is room for at least wcslen(src)+1 wide characters at dest.
wcpcpy returns a pointer to the end of the wide-character string dest, that is, a pointer to the terminating L'\0' character.