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| 57 | <body lang="en">
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| 58 | <span id="Static-Functions"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Arrays-as-Parameters.html" accesskey="n" rel="next">Arrays as Parameters</a>, Previous: <a href="Forward-Function-Declarations.html" accesskey="p" rel="prev">Forward Function Declarations</a>, Up: <a href="Function-Definitions.html" accesskey="u" rel="up">Function Definitions</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="Static-Functions-1"></span><h4 class="subsection">22.1.3 Static Functions</h4>
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| 64 | <span id="index-static-functions"></span>
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| 65 | <span id="index-functions_002c-static"></span>
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| 66 | <span id="index-static-1"></span>
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| 67 |
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| 68 | <p>The keyword <code>static</code> in a function definition limits the
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| 69 | visibility of the name to the current compilation module. (That’s the
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| 70 | same thing <code>static</code> does in variable declarations;
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| 71 | see <a href="File_002dScope-Variables.html">File-Scope Variables</a>.) For instance, if one compilation module
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| 72 | contains this code:
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| 73 | </p>
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| 74 | <div class="example">
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| 75 | <pre class="example">static int
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| 76 | foo (void)
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| 77 | {
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| 78 | <span class="roman">…</span>
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| 79 | }
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| 80 | </pre></div>
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| 81 |
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| 82 | <p>then the code of that compilation module can call <code>foo</code> anywhere
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| 83 | after the definition, but other compilation modules cannot refer to it
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| 84 | at all.
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| 85 | </p>
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| 86 | <span id="index-forward-declaration"></span>
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| 87 | <span id="index-static-function_002c-declaration"></span>
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| 88 | <p>To call <code>foo</code> before its definition, it needs a forward
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| 89 | declaration, which should use <code>static</code> since the function
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| 90 | definition does. For this function, it looks like this:
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| 91 | </p>
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| 92 | <div class="example">
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| 93 | <pre class="example">static int foo (void);
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| 94 | </pre></div>
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| 95 |
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| 96 | <p>It is generally wise to use <code>static</code> on the definitions of
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| 97 | functions that won’t be called from outside the same compilation
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| 98 | module. This makes sure that calls are not added in other modules.
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| 99 | If programmers decide to change the function’s calling convention, or
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| 100 | understand all the consequences of its use, they will only have to
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| 101 | check for calls in the same compilation module.
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| 102 | </p>
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| 103 |
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| 104 |
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| 105 |
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