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一般</th></tr><tr><td class="sidebar-content" style="text-align: left">
<ul><li><a href="Stdlib.h#数据类型" title="Stdlib.h">数据类型</a></li>
<li><a href="Ctype.h" title="Ctype.h">字符类型</a></li>
<li><a href="String.h" title="String.h">字符串</a></li>
<li><a href="Math.h" title="Math.h">数学</a></li>
<li><a href="Stdio.h" title="Stdio.h">文件输入/输出</a></li>
<li><a href="Time.h" title="Time.h">日期/时间</a></li>
<li><a href="Locale.h" title="Locale.h">本地化</a></li>
<li><a href="Stdlib.h#函数" title="Stdlib.h">内存分配</a></li>
<li><a href="Stdlib.h#函数" title="Stdlib.h">过程控制</a></li>
<li><a href="Signal.h" title="Signal.h">信号</a></li>
<li><a href="C%E6%9B%BF%E4%BB%A3%E6%A0%87%E8%AE%B0" title="C替代标记">替代标记</a></li></ul></td>
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杂项</th></tr><tr><td class="sidebar-content" style="text-align: left">
<ul><li><code>&lt;<a href="Assert.h" title="Assert.h">assert.h</a>&gt;</code></li>
<li><code>&lt;<a href="Errno.h" title="Errno.h">errno.h</a>&gt;</code></li>
<li><code>&lt;<a href="Setjmp.h" title="Setjmp.h">setjmp.h</a>&gt;</code></li>
<li><code>&lt;<a href="Stdarg.h" title="Stdarg.h">stdarg.h</a>&gt;</code></li></ul></td>
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<p><b><code>stddef.h</code></b>是<a href="C%E6%A8%99%E6%BA%96%E5%87%BD%E6%95%B8%E5%BA%AB" class="mw-redirect" title="C標準函數庫">C標準函数庫</a>中的<a href="%E5%A4%B4%E6%96%87%E4%BB%B6" title="头文件">头文件</a>，定义了若干常见的类型与宏。   
</p>
<div class="mw-heading mw-heading2"><h2 id="类型"><span id=".E7.B1.BB.E5.9E.8B"></span>类型</h2></div>
<ul><li>ptrdiff_t 有符号整数型</li>
<li>size_t 无符号整数型</li>
<li>wchar_t 16位或32位整数型</li></ul>
<div class="mw-heading mw-heading2"><h2 id="宏"><span id=".E5.AE.8F"></span>宏</h2></div>
<ul><li>NULL  与实现相关的空指针的值</li>
<li><a href="Offsetof" title="Offsetof">offsetof</a>(type, member-designator)  结构体内成员的偏移量</li></ul>
<div class="mw-heading mw-heading2"><h2 id="参考文献"><span id=".E5.8F.82.E8.80.83.E6.96.87.E7.8C.AE"></span>参考文献</h2></div>
<div class="reflist" style="list-style-type: decimal;">
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