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<title>Binary constants (Using the GNU Compiler Collection (GCC))</title>

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<a name="Binary-Constants-using-the-0b-Prefix"></a>
<h3 class="section">6.65 Binary Constants using the &lsquo;<samp>0b</samp>&rsquo; Prefix</h3>
<a name="index-Binary-constants-using-the-0b-prefix"></a>

<p>Integer constants can be written as binary constants, consisting of a
sequence of &lsquo;<samp>0</samp>&rsquo; and &lsquo;<samp>1</samp>&rsquo; digits, prefixed by &lsquo;<samp>0b</samp>&rsquo; or
&lsquo;<samp>0B</samp>&rsquo;.  This is particularly useful in environments that operate a
lot on the bit level (like microcontrollers).
</p>
<p>The following statements are identical:
</p>
<div class="smallexample">
<pre class="smallexample">i =       42;
i =     0x2a;
i =      052;
i = 0b101010;
</pre></div>

<p>The type of these constants follows the same rules as for octal or
hexadecimal integer constants, so suffixes like &lsquo;<samp>L</samp>&rsquo; or &lsquo;<samp>UL</samp>&rsquo;
can be applied.
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