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| <h3 class="section">A.2 Variadic Functions</h3> |
| |
| <p><a name="index-variable-number-of-arguments-3709"></a><a name="index-variadic-functions-3710"></a><a name="index-optional-arguments-3711"></a> |
| ISO C<!-- /@w --> defines a syntax for declaring a function to take a variable |
| number or type of arguments. (Such functions are referred to as |
| <dfn>varargs functions</dfn> or <dfn>variadic functions</dfn>.) However, the |
| language itself provides no mechanism for such functions to access their |
| non-required arguments; instead, you use the variable arguments macros |
| defined in <samp><span class="file">stdarg.h</span></samp>. |
| |
| <p>This section describes how to declare variadic functions, how to write |
| them, and how to call them properly. |
| |
| <p><strong>Compatibility Note:</strong> Many older C dialects provide a similar, |
| but incompatible, mechanism for defining functions with variable numbers |
| of arguments, using <samp><span class="file">varargs.h</span></samp>. |
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| <ul class="menu"> |
| <li><a accesskey="1" href="Why-Variadic.html#Why-Variadic">Why Variadic</a>: Reasons for making functions take |
| variable arguments. |
| <li><a accesskey="2" href="How-Variadic.html#How-Variadic">How Variadic</a>: How to define and call variadic functions. |
| <li><a accesskey="3" href="Variadic-Example.html#Variadic-Example">Variadic Example</a>: A complete example. |
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