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    <p>This:</p> <pre><code> progList = &amp;list[0]; </code></pre> <p>Should work perfectly.</p> <p>But because:</p> <pre><code>std::vector&lt;char*&gt; list; </code></pre> <p>is local to the function it is only valid while the function is active. Once the function returns the pointer become invalid (as the vector no longer exists).</p> <p>The reason I mention this is that you seem to be trying to use <code>progList</code> as an out parameters here:</p> <pre><code>int glfxGetProgramList(int effect, char** progList, int* count) // Because you call like this: glfxGetProgramList(effect, list, &amp;size ); // The value of list will not change // as you are passing by value. fprintf(stderr, "Output: %s\n", list[0]); // So here list has not changed. // But also note it would not have worked // as the object you were trying to make it // point at would have gone out of scope. </code></pre> <p>Unfortunately (or fortunately) because these parameters are not references any changes you make locally do not affect the original values outside the function.</p> <p>So you need to fix a couple of things:</p> <ul> <li>Make the vector last longer than the call to the function</li> <li>Pass list by reference into the function.</li> </ul> <p>Try:</p> <pre><code>int glfxGetProgramList(int effect, char**&amp; progList, int* count) // ^ pass by reference { static std::vector&lt;char*&gt; list; // Static makes the list last past the end of the function list.clear(); // Now we have to clear it each time we call to make sure // that old results do not pollute the list. gEffects[effect]-&gt;GetProgramList(list); fprintf(stderr, "Lib Output: %s\n", list[0]); progList = &amp;list[0]; // Value now passed correctly // back to the calling function // and list will still exist. int size = list.size(); memcpy(count, &amp;size, sizeof(int)); // This copies the first value out } </code></pre>
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    1. POHow to convert std::vector<char*> to char**?
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    1. USMartin York
    1. USMartin York
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    1. POHow to convert std::vector<char*> to char**?
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    1. COYeah, I figured that out but do you have any ideas for a solution? Actually I think I need to post the code for GetProgramList. Editing now...
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      1. USSteveDeFacto
    2. COYeah, that works. Ugly as hell but it will do!
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      1. USSteveDeFacto
    3. COThat static vector is an accident waiting to happen. Why not simply `int glfxGetProgramList(int effect, vector<char*>& list)`?
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      1. USGuy Sirton
 

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