code: func (c *PipeConn) Write(b []byte) (int, error) {
  	overlapped, err := newOverlapped()
  	if err != nil {
  		return 0, err
  	}
  	defer syscall.CloseHandle(overlapped.HEvent)
  	var n uint32
  	err = syscall.WriteFile(c.handle, b, &n, overlapped)
  	return c.completeRequest(iodata{n, err}, c.writeDeadline, overlapped)
  }
docs: // Write implements the net.Conn Write method.