Re: Does push_back() do a copy?

From:
Stefan Naewe <nospam@please.net>
Newsgroups:
comp.lang.c++
Date:
Thu, 28 Jun 2007 13:03:42 +0200
Message-ID:
<h5hcl4-0rm.ln1@news01.atlas.de>
On 6/28/2007 12:52 PM, Angus wrote:

I have a socket class CTestClientSocket which I am using to simulate
load testing.

I create multiple instances of the client like this:

for (int i = 0; i < 5; i++)
{
    CTestClientSocket* pTemp = new CTestClientSocket(this, ip, port);
    pTemp->Connect();
    m_collClients.push_back(pTemp);
// delete pTemp;
}

Note I have commented out the delete pTemp

Then I send some data to a server like this:

// iterate through collection of clients
for (std::vector<CTestClientSocket*>::iterator it =
m_collClients.begin();
    it != m_collClients.end(); it++)
    {
        (*it)->Send(byData);
    }

This works if delete pTemp on the Connect is commented out. But I
thought that push_back would make a copy of pTemp.


And what happens if you copy a pointer ?

and so I could
then delete pTemp. But if I delete pTemp I get an memory access
problem in the (*it)->Send(byData);


Because you have a dangling pointer.

And I have to cleanup at the end. Does push_back NOT do a copy? I am
confused, can someone explain.

Or is there a better way to do this sort of thing?


Use boost::shared_ptr<> for example.

S.
--
Stefan Naewe stefan dot naewe at atlas-elektronik dot com
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