Re: Deleting exceptions after throwing

From:
pjb@informatimago.com (Pascal J. Bourguignon)
Newsgroups:
comp.lang.c++
Date:
Thu, 24 Sep 2009 14:18:44 +0200
Message-ID:
<7c8wg4o7rv.fsf@pbourguignon.lefevre.anevia.com>
Emil Berg <emilbergg@gmail.com> writes:

On Sep 24, 1:57 pm, Alan Woodland <aj...@aber.ac.uk> wrote:

Emil Berg wrote:

[snip]

What I want to do is pass exceptions between threads. I have some
exception classes that derive from CBaseException class.
Now I'm doing the following steps:
1. Throw FileNotFoundException on thread A
2. Catch it as CBaseException and save it in an CBaseException*
pointer.
3. Pass this pointer to thread B
4. Throw this exception manually.
5. Catching the exception on thread B as FileNotFoundException
reference

Steps 2,3,4 are part of a threading/messaging infrastructure that I'm
building, so I'd like to delete the exception on thread B after
throwing it (inside the infrastructure).
I don't want the user to delete the exception.

I hope that I explained it well and maybe you have a good idea to
solve it.


Why not use something like auto_ptr around step 4 so that when you hit
the throw it gets deleted during stack unwinding?

Alan


If I throw auto_ptr<FileNotFoundException> then the user needs to
catch auto_ptr<FileNotFoundException>.
I want the user to catch just FileNotFoundException and not its
auto_ptr.


class TheActualFileNotFoundException:public std::exception {
....
};
typedef auto_ptr<TheActualFileNotFoundException> FileNotFoundException;

--
__Pascal Bourguignon__

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