🚀 go-pugleaf

I attempt to implement a stream for message boxes.
First the example:

   class MessageBuffer : public strstreambuf
   {
      public:
      MessageBuffer()
      : strstreambuf()
      {}
	  
	  // ... more constructors
      
      virtual int sync()                   // *** First question *** //
	  {
	     // Target specific implementation.
		 // A simple example:
	     cout << this; return __NOT_EOF;
	  }
   };
   
   class Message : public ostrstream
   {
      public:
      Message()
      : ostrstream()
      { init(new MessageBuffer); }          // *** Second question *** //
      
	  // ... more constructors
   };

First question:
The function sync() should only executed if ostream::flush() is called. However i am not sure. 
Are there any side effects ?

Second question:
Deletes ~ios() any the streambuffer object or is it a job for ~Message() ?

Thanks
Danke schoen
   Dieter Luecking