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| 22 | <title>Intertwined Incomplete Types (GNU C Language Manual)</title>
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| 32 | <link href="Structures.html" rel="up" title="Structures">
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| 57 | <body lang="en">
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| 58 | <span id="Intertwined-Incomplete-Types"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Type-Tags.html" accesskey="n" rel="next">Type Tags</a>, Previous: <a href="Incomplete-Types.html" accesskey="p" rel="prev">Incomplete Types</a>, Up: <a href="Structures.html" accesskey="u" rel="up">Structures</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="Intertwined-Incomplete-Types-1"></span><h3 class="section">15.19 Intertwined Incomplete Types</h3>
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| 64 |
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| 65 | <p>When several structure types contain pointers to each other, you can
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| 66 | define the types in any order because pointers to types that come
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| 67 | later are incomplete types. Thus,
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| 68 | Here is an example.
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| 69 | </p>
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| 70 | <div class="example">
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| 71 | <pre class="example">/* <span class="roman">An employee record points to a group.</span> */
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| 72 | struct employee
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| 73 | {
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| 74 | char *name;
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| 75 | <span class="roman">…</span>
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| 76 | struct group *group; /* <span class="roman">incomplete type.</span> */
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| 77 | <span class="roman">…</span>
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| 78 | };
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| 79 |
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| 80 | /* <span class="roman">An employee list points to employees.</span> */
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| 81 | struct employee_list
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| 82 | {
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| 83 | struct employee *this_one;
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| 84 | struct employee_list *next; /* <span class="roman">incomplete type.</span> */
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| 85 | <span class="roman">…</span>
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| 86 | };
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| 87 |
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| 88 | /* <span class="roman">A group points to one employee_list.</span> */
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| 89 | struct group
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| 90 | {
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| 91 | char *name;
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| 92 | <span class="roman">…</span>
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| 93 | struct employee_list *employees;
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| 94 | <span class="roman">…</span>
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| 95 | };
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| 96 | </pre></div>
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| 97 |
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| 98 |
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| 99 |
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| 100 |
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| 101 | </body>
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| 102 | </html>
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