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    <p>Assuming that <code>X</code> is the type of the objects in the list, then you can do something like this:</p> <pre><code>void DoSomething(X&amp; object) { object.count, object.avg; } void DoSomethingElse(int&amp; count, int&amp; average) { ... } int main() { ... for(std::list&lt;X&gt;::iterator it=myList.begin(), end=myList.end(); it != end; ++it) { DoSomething(*it); // how I'd do it DoSomethingElse(it-&gt;count, it-&gt;avg); // Equally valid way that you did it } ... } </code></pre> <p>Just remember:</p> <ul> <li><code>container.begin()</code> is the a pointer to the first element</li> <li><code>container.end()</code> is a pointer to one-past-the-last element</li> <li><code>*it</code> is a reference to the pointed-to element</li> <li><code>it != container.end()</code> is how you tell if you are at the end</li> <li><code>it-&gt;x</code> is a member of the pointed-to element</li> <li>removing an object from a container might invalidate outstanding iterators, depending upon several factors.</li> <li><code>++it</code> is probably more efficient than <code>it++</code></li> </ul> <hr> <p><strong>EDIT</strong>: OP asks:</p> <blockquote> <blockquote> <p>I'm not iterating through the list and running calc_average on every single node, but rather iterating through the list looking for a specific item value. Once I find the one of interest, I'm calling the calc_average function on that specific node. I just don't need to have the for loop. Instead I would arrive at my desired iterator, and pass that via *it to void DoSomething ?</p> </blockquote> </blockquote> <p>I think you understand how it works now. You'd have some code to search for the indicated node, and then some other code to invoke your function:</p> <pre><code> std::list&lt;X&gt;::iterator it, end; for(it=myList.begin(), end=myList.end(); it != end; ++it) { // Look for the special node: if( it-&gt;magicValue == 42 ) { // We found it! break; } } // Either it is equal to end (boo!) or it points to the special node (yay!) if( it == end ) { std::cerr &lt;&lt; "Could not find special node!\n"; } if( it != end ) { DoSomething(*it); } </code></pre>
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    1. POHow do I pass struct members stored in a list to a function by reference?
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    1. POHow do I pass struct members stored in a list to a function by reference?
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    1. COThanks, this helps. Let me clarify something though. I'm not iterating through the list and running `calc_average` on every single node, but rather iterating through the list looking for a specific `item` value. Once I find the one of interest, I'm calling the `calc_average` function on that specific node, call it node #5 in my list. As I write this, I think your suggestion still works though, right? I just don't need to have the `for` loop. Instead I would arrive at my desired iterator, and pass that via `*it` to `void DoSomething` ? Will try this later tonight, but this helps a ton!
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    2. COSee recent edit.
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    3. COOne more question...if I make a function call like `DoSomething(it)`, will that just pass the pointed-to element by value? I ask because I have another output function where nothing is being written to the struct, but instead I'm just printing member values to the screen. Thx
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