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    <p>The problem you have is that you haven't looked at copy construction and copy assignment: when you push an object into a <code>std::vector&lt;T&gt;</code> it gets copied and the objects with the <code>std::vector&lt;T&gt;</code> get possibly moved around using assignment. The default generated copy constructor and copy assignment just copy or assign the respective members, i.e., whenever either copy is used, you'd end up with two objects pointing to the same <code>buf</code>. The first one destroyed would use <code>delete[] buf;</code> and all others would have a stale pointer which can't be deleted again. That is, you want to add three methods to your <code>packetQueue</code>:</p> <pre><code>struct packetQueue { packetQueue(packetQueue const&amp; other); // copy constructor: copies the content packetQueue&amp; operator= (packetQueue const&amp; other); //copy assignment: updates the content ~packetQueue() // destructor: release the memory void swap(packetQueue&amp; other); // swap the content // other members }; </code></pre> <p>To leverage the copy construction and destruction in the copy assignment, I find it useful to have a <code>swap()</code> member, because this is easily implemented and makes for a nice, simple copy assignment:</p> <pre><code>void packetQueue::swap(packetQueue&amp; other) { std::swap(this-&gt;buf, other.buf); std::Swap(this-&gt;size, other.size); } packetQueue&amp; packetQueue::operator= (packetQueue const&amp; other) { packetQueue(other).swap(*this); return *this; } </code></pre>
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    1. POFinding Reason For Memory Leaking With Char*
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    1. USDietmar Kühl
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    1. COBut for example, my program keeps copying from one vector to another, it will be a little bad for my perfomance to keep copying everything? Yeah, I know about the rule of four, have some many names, but I'm not sure in this case.
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    2. COThere are three approaches how to deal with resources: the simplest is the copying I described above. If you can't copy you can reference count your resources which can be more efficient but is harder to get right. Finally, if you can use C++ 2011 you can move objects instead copying them. This needs playing a coupe of tricks which are also non-trivial. Personally, I would start with the simplest approach and deal with issues if this, indeed, turns out to be too slow.
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