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<p><code>extrn</code> declarations.</p>

<p><big>extern</big></p>
<p>To understand how external variables relate to the <code>extern</code> keyword, it is necessary to know the difference between defining and declaring a variable. When a variable is defined, the <a href="page.php?w=compiler">compiler</a> allocates memory for that variable and possibly also initializes its contents to some value. When a variable is declared, the compiler requires that the variable be defined elsewhere. The declaration informs the compiler that a variable by that name and</p><p>
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