sp; // 为了创建新的安全描述符 pNewSd 而得到各项的长度
    //
    if ( GetLastError() == ERROR_INSUFFICIENT_BUFFER )
    {
      pOldDAcl = ( PACL ) HeapAlloc( GetProcessHeap(),
                                     HEAP_ZERO_MEMORY,
                                     dwAclSize );
      pSacl = ( PACL ) HeapAlloc( GetProcessHeap(),
                                  HEAP_ZERO_MEMORY,
                                  dwSaclSize );
      pSidOwner = ( PSID ) HeapAlloc( GetProcessHeap(),
                                      HEAP_ZERO_MEMORY,
                                      dwSidOwnLen );
      pSidPrimary = ( PSID ) HeapAlloc( GetProcessHeap(),
                                        HEAP_ZERO_MEMORY,
                                        dwSidPrimLen );
      pNewSd = ( PSECURITY_DESCRIPTOR ) HeapAlloc( GetProcessHeap(),
                                                   HEAP_ZERO_MEMORY,
                           &n