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58<span id="Variable-Declarations"></span><div class="header">
59<p>
60Next: <a href="Initializers.html" accesskey="n" rel="next">Initializers</a>, Up: <a href="Variables.html" accesskey="u" rel="up">Variables</a> &nbsp; [<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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63<span id="Variable-Declarations-1"></span><h3 class="section">20.1 Variable Declarations</h3>
64<span id="index-variable-declarations"></span>
65<span id="index-declaration-of-variables"></span>
66
67<p>Here&rsquo;s what a variable declaration looks like:
68</p>
69<div class="example">
70<pre class="example"><var>keywords</var> <var>basetype</var> <var>decorated-variable</var> <span class="roman">[</span>= <var>init</var><span class="roman">]</span>;
71</pre></div>
72
73<p>The <var>keywords</var> specify how to handle the scope of the variable
74name and the allocation of its storage. Most declarations have
75no keywords because the defaults are right for them.
76</p>
77<p>C allows these keywords to come before or after <var>basetype</var>, or
78even in the middle of it as in <code>unsigned static int</code>, but don&rsquo;t
79do that&mdash;it would surprise other programmers. Always write the
80keywords first.
81</p>
82<p>The <var>basetype</var> can be any of the predefined types of C, or a type
83keyword defined with <code>typedef</code>. It can also be <code>struct
84<var>tag</var></code>, <code>union <var>tag</var></code>, or <code>enum <var>tag</var></code>. In
85addition, it can include type qualifiers such as <code>const</code> and
86<code>volatile</code> (see <a href="Type-Qualifiers.html">Type Qualifiers</a>).
87</p>
88<p>In the simplest case, <var>decorated-variable</var> is just the variable
89name. That declares the variable with the type specified by
90<var>basetype</var>. For instance,
91</p>
92<div class="example">
93<pre class="example">int foo;
94</pre></div>
95
96<p>uses <code>int</code> as the <var>basetype</var> and <code>foo</code> as the
97<var>decorated-variable</var>. It declares <code>foo</code> with type
98<code>int</code>.
99</p>
100<div class="example">
101<pre class="example">struct tree_node foo;
102</pre></div>
103
104<p>declares <code>foo</code> with type <code>struct tree_node</code>.
105</p>
106<table class="menu" border="0" cellspacing="0">
107<tr><td align="left" valign="top">&bull; <a href="Declaring-Arrays-and-Pointers.html" accesskey="1">Declaring Arrays and Pointers</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Declaration syntax for variables of
108 array and pointer types.
109</td></tr>
110<tr><td align="left" valign="top">&bull; <a href="Combining-Variable-Declarations.html" accesskey="2">Combining Variable Declarations</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">More than one variable declaration
111 in a single statement.
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