code: func (c *Callbacks) OnCNETMsg_SplitScreenUser(fn func(*dota.CNETMsg_SplitScreenUser) error) {
  	c.onCNETMsg_SplitScreenUser = append(c.onCNETMsg_SplitScreenUser, fn)
  }
docs: // OnCNETMsg_SplitScreenUser registers a callback for NET_Messages_net_SplitScreenUser