I was wondering if the below function prototype is valid. It compiled fine, but the three period is kinda throwing me off and I couldn't find anything similar on Google.
void foo(int, ...);
Thanks!
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http://stackoverflow.com/questions/7317811/how-to-use-variable-argument – NaCl Nov 05 '14 at 22:32
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To google it don't forget to provide `...` like this in search criteria: `"..."` – πάντα ῥεῖ Nov 05 '14 at 22:34
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By the way, the C++ standard says "ellipsis" rather than "ellipse" or "ellipses" which may be contrary to your google efforts. – Nov 05 '14 at 22:34
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Ah, I see. Thanks for the tips guys. And sorry for making a duplicate question. – Jonathan DInh Nov 05 '14 at 22:41
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Yes, it's valid. In this example, ... creates a variadic function using the va_list mechanism. This is how variadic functions are implemented in C, and to some degree in C++ (though C++11's template parameter packs have rendered this mechanism obsolete).
Further reading: va_arg
cdhowie
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