code: func (c *Conn) CloseWrite() error {
  	if terr := c.ep.Shutdown(tcpip.ShutdownWrite); terr != nil {
  		return c.newOpError("close", errors.New(terr.String()))
  	}
  	return nil
  }
docs: // CloseWrite shuts down the writing side of the TCP connection. Most callers
  // should just use Close.
  //
  // A TCP Half-Close is performed the same as CloseWrite for *net.TCPConn.