pub unsafe extern "C" fn CSTL_wstring_copy(
instance: CSTL_WideStringCRef,
dest: *mut wchar_t,
count: usize,
off: usize,
) -> usizeExpand description
Copies a substring [off, off + count) to character string pointed to by
dest. The resulting character string is not null terminated.
Returns the number of characters copied or CSTL_string_npos if
off > CSTL_wstring_size(instance) (out of range).