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| 32 | <link href="Functions.html" rel="up" title="Functions">
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| 58 | <span id="Function-Definitions"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Function-Declarations.html" accesskey="n" rel="next">Function Declarations</a>, Up: <a href="Functions.html" accesskey="u" rel="up">Functions</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Index.html" title="Index" rel="index">Index</a>]</p>
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| 61 | </div>
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| 62 | <hr>
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| 63 | <span id="Function-Definitions-1"></span><h3 class="section">22.1 Function Definitions</h3>
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| 64 | <span id="index-function-definitions"></span>
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| 65 | <span id="index-defining-functions"></span>
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| 66 |
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| 67 | <p>We have already presented many examples of function definitions. To
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| 68 | summarize the rules, a function definition looks like this:
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| 69 | </p>
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| 70 | <div class="example">
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| 71 | <pre class="example"><var>returntype</var>
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| 72 | <var>functionname</var> (<var>parm_declarations</var><span class="roman">…</span>)
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| 73 | {
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| 74 | <var>body</var>
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| 75 | }
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| 76 | </pre></div>
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| 77 |
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| 78 | <p>The part before the open-brace is called the <em>function header</em>.
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| 79 | </p>
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| 80 | <p>Write <code>void</code> as the <var>returntype</var> if the function does
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| 81 | not return a value.
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| 82 | </p>
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| 83 | <table class="menu" border="0" cellspacing="0">
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| 84 | <tr><td align="left" valign="top">• <a href="Function-Parameter-Variables.html" accesskey="1">Function Parameter Variables</a></td><td> </td><td align="left" valign="top">Syntax and semantics
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| 85 | of function parameters.
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| 86 | </td></tr>
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| 87 | <tr><td align="left" valign="top">• <a href="Forward-Function-Declarations.html" accesskey="2">Forward Function Declarations</a></td><td> </td><td align="left" valign="top">Functions can only be called after
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| 88 | they have been defined or declared.
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| 89 | </td></tr>
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| 90 | <tr><td align="left" valign="top">• <a href="Static-Functions.html" accesskey="3">Static Functions</a></td><td> </td><td align="left" valign="top">Limiting visibility of a function.
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| 91 | </td></tr>
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| 92 | <tr><td align="left" valign="top">• <a href="Arrays-as-Parameters.html" accesskey="4">Arrays as Parameters</a></td><td> </td><td align="left" valign="top">Functions that accept array arguments.
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| 93 | </td></tr>
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| 94 | <tr><td align="left" valign="top">• <a href="Structs-as-Parameters.html" accesskey="5">Structs as Parameters</a></td><td> </td><td align="left" valign="top">Functions that accept structure arguments.
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| 95 | </td></tr>
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| 96 | </table>
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| 97 |
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