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    <p>The second parameter of signal should be a pointer to a function accepting an int and returning void. What you're passing to signal is a pointer to a <em>member</em> function accepting an int and returning void (its type being <code>void (myClass::*)(int)</code>). I can see three possibilities to overcome this issue:</p> <p>1 - Your method <code>myHandler</code> can be static: this is great, make it static</p> <pre><code>class myClass { public: void myFunction () { signal(SIGIO, myClass::myHandler); } static void myHandler (int signum) { // handling code } }; </code></pre> <p>2 - Your method shouldn't be static: if you're planning to use signal with only one instance, you can create a private static object, and write a static method that simply call the method on this object. Something along the lines of</p> <pre><code>class myClass { public: void myFunction () { signal(SIGIO, myClass::static_myHandler); } void myHandler (int signum) { // handling code } static void static_myHandler(int signum) { instance.myHandler(signum); } private: static myClass instance; }; </code></pre> <p>3 - However, if you're planning on using the signal with multiple instances, things will get more complicated. Perhaps a solution would be to store each instance you want to manipulate in a static vector, and invoking the method on each of these :</p> <pre><code>class myClass { public: void myFunction () // registers a handler { instances.push_back(this); } void myHandler (int signum) { // handling code } static void callHandlers (int signum) // calls the handlers { std::for_each(instances.begin(), instances.end(), std::bind2nd(std::mem_fun(&amp;myClass::myHandler), signum)); } private: static std::vector&lt;myClass *&gt; instances; }; </code></pre> <p>and somewhere, do a single call to</p> <pre><code>signal(SIGIO, myClass::callHandlers); </code></pre> <p>But I think that if you end up using the last solution, you should probably think about changing your handling design :-)!</p>
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    1. POIs it possible to use signal inside a C++ class?
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    1. USLuc Touraille
    1. USLuc Touraille
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    1. COYour second example isn't standard C++.
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    2. COIs that because I forgot the static keyword? If so, it's corrected!
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