docs: public static int copyWriterCount(final Reader in, final Writer out) throws IOException {
          final char[] buffer = new char[10240];
          int tot=0;
          int c;
          c = in.read(buffer);
          while (c >= 0) {
              if (c > 0) {
                  out.write(buffer, 0, c);
                  tot += c;
              }
              c = in.read(buffer);
          }
          return tot;
      }