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Modification to #2
>
> There are two (or three) errata in the Streams example
> in C++NPv2 on p302.
>
> When a module contains a member variable task that it
> passes to its base class:
>
> Given the following typedef:
>
> typedef ACE_Module parent;
>
> 1. The base class default constructor must be used in
> the constructor initialization list (i.e., don't put
> anything in the constructor list, or put parent() to
> be explicit about it), and then the base
> class parent::open() function should be used in the
> body of the derived module constructor to pass
> the address of the member variable task.
>
> This ensures that the member variable task has
> finished construction before being passed to the
> base class.
>
> 2. The derived module must implement a destructor,
> and that destructor must call parent::close().
> This removes any reference to the member
> variable in the base class, and avoids a SEGV
> when the base class destructor is closed.
Just calling close() (inherited) is ok.
The code in Module.cpp, close_i, makes a call
task->module_closed() which will SEGV if the
base class destructor calls close_i() since
the inherited class has already been destroyed
(it contained the member class referred to
by this task pointer).
> 3. A possible third errata is that the flag passed
> to the base class tells the base class parent::close()
> which task to delete. In the example, no tasks should
> be deleted, so the flag should probably
> be parent::M_DELETE_NONE.
>
> Regards
> Dave
>
>
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