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accessing the vtable

Hello, I was wondering if it were possible to access the vtable directly.
Are there any resources that detail the inner workings of the vtable?
Jul 22 '05 #1
6 2510
2004-7-20 14:25:59

Nolan Martin <mo**********@h otmail.com> wrote in message

<XV2Lc.60214$Mr 4.56908@pd7tw1n o>
Hello, I was wondering if it were possible to access the vtable directly.
Are there any resources that detail the inner workings of the

vtable?

I think even if you find the virtual table through the "hiden" member
variebles,you can do nothing to the content of the table,since that
you don't know exactly the order of the pointer to the virtual
methods,don't you?
--
Composed with Newz Crawler 1.7 http://www.newzcrawler.com/
Jul 22 '05 #2
* Nolan Martin:

Hello, I was wondering if it were possible to access the vtable directly.
A C++ implementation need not be based on using vtables.

Windows C++ compilers are as a rule vtable-based with access to the
vtable for simple objects (in order to support Windows COM technology).

However, since you're asking about this it is 100% sure that you _don't_
need such access -- try instead to explain what you're trying to
achieve, and if you succeed in explaining that (some code that compiles
is recommended) you will get answers that will help you do whatever.

Are there any resources that detail the inner workings of the vtable?


Yes. ;-)

--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
Jul 22 '05 #3
> > Hello, I was wondering if it were possible to access the vtable
directly.
Are there any resources that detail the inner workings of the

vtable?

I think even if you find the virtual table through the "hiden" member
variebles,you can do nothing to the content of the table,since that
you don't know exactly the order of the pointer to the virtual
methods,don't you?


I dont want to modify the data, just read it.
Jul 22 '05 #4
2004-7-20 14:50:41

"Alf P. Steinbach" <al***@start.no > wrote in message

<40************ ****@news.indiv idual.net>
* Nolan Martin:
Hello, I was wondering if it were possible to access the vtable directly.
A C++ implementation need not be based on using vtables. Windows C++ compilers are as a rule vtable-based with access to the vtable for simple objects (in order to support Windows COM technology).
However, since you're asking about this it is 100% sure that you _don't_
need such access -- try instead to explain what you're trying to achieve, and if you succeed in explaining that (some code that compiles
is recommended) you will get answers that will help you do whatever.
Are there any resources that detail the inner workings of the

vtable?
Yes. ;-) -- A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail?


What resouce? Can you show me how to get it?

many thanks!
--
Composed with Newz Crawler 1.7 http://www.newzcrawler.com/
Jul 22 '05 #5
Stone Lan wrote:
What resouce? Can you show me how to get it?


The book /Inside the C++ Object Model/ by Lippman, IIRC.

--
Phlip
http://industrialxp.org/community/bi...UserInterfaces
Jul 22 '05 #6
On Tue, 20 Jul 2004 15:05:55 +0800, Stone Lan <st*********@ho tmail.com>
wrote:
> Are there any resources that detail the inner workings of the

vtable?

Yes. ;-)



What resouce? Can you show me how to get it?

many thanks!


Here is one example

http://www.codesourcery.com/cxx-abi/abi.html#vtable

john
Jul 22 '05 #7

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