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<h1><img src="../../boost.png" alt="boost.png (6897 bytes)" align="center" width="277" height="86">Header
boost/cstdint.hpp&nbsp;</h1>
<p>The header <code><a href="../../boost/cstdint.hpp">&lt;boost/cstdint.hpp&gt;</a></code>
provides the typedef's useful for
writing portable code that requires certain integer widths.  All typedef's are in namespace boost.</p>
<p>The specifications are based on the ISO/IEC 9899:1999 C Language standard
header &lt;stdint.h&gt;.&nbsp; The 64-bit types required by the C standard are not
required in the boost header, and may not be supplied in all implementations,
because <code>long long</code> is not [yet] included in the C++ standard.</p>
<p>See <a href="cstdint_test.cpp">cstdint_test.cpp</a> for a test program.</p>
<h2>Exact-width integer types</h2>
<p>The typedef <code>int#_t</code>, with # replaced by the width, designates a
signed integer type of exactly # bits; <code>int8_t</code> denotes an 8-bit
signed integer type.&nbsp; Similarly, the typedef <code>uint#_t</code>
designates and unsigned integer type of exactly # bits.</p>
<p>These types are optional. However, if an implementation provides integer
types with widths of 8, 16, 32, or 64 bits, it shall define the corresponding
typedef names.</p>
<h2>Minimum-width integer types</h2>
<p>The typedef <code>int_least#_t</code>, with # replaced by the width,&nbsp;
designates a signed integer type with a width of at least # bits, such that no
signed integer type with lesser size has at least the specified width. Thus, <code>int_least32_t</code>
denotes a signed integer type with a width of at least 32 bits. Similarly, the
typedef name <code>uint_least#_t</code> designates an unsigned integer type with
a width of at least # bits, such that no unsigned integer type with lesser size
has at least the specified width.</p>
<p>Required minimum-width integer types:</p>
<ul>
  <li><code>int_least8_t</code></li>
  <li><code>int_least16_t</code></li>
  <li><code>int_least32_t</code></li>
  <li><code>uint_least8_t</code></li>
  <li><code>uint_least16_t</code></li>
  <li><code>uint_least32_t</code></li>
</ul>
<p>All other minimum-width integer types are optional.</p>
<h2>Fastest minimum-width integer types</h2>
<p>The typedef <code>int_fast#_t</code>, with # replaced by the width,
designates the fastest signed integer type with a width of at least # bits.
Similarly, the typedef name <code>uint_fast#_t</code> designates the fastest
unsigned integer type with a width of at least # bits.</p>
<p>There is no guarantee that these types are fastest for all purposes.&nbsp; In
any case, however, they satisfy&nbsp; the signedness and width requirements.</p>
<p>Required fastest minimum-width integer types:</p>
<ul>
  <li><code>int_fast8_t</code></li>
  <li><code>int_fast16_t</code></li>
  <li><code>int_fast32_t</code></li>
  <li><code>uint_fast8_t</code></li>
  <li><code>uint_fast16_t</code></li>
  <li><code>uint_fast32_t</code></li>
</ul>
<p>All other fastest minimum-width integer types are optional.</p>
<h2>Greatest-width integer types</h2>
<p>The typedef <code>intmax_t </code>designates a signed integer type capable of
representing any value of any signed integer type.</p>
<p>The typedef <code>uintmax_t</code> designates an unsigned integer type
capable of representing any value of any unsigned integer type.</p>
<p>These types are required.</p>
<hr>
<p>Revised <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %b %Y" startspan -->06 Nov 2007<!--webbot bot="Timestamp" endspan i-checksum="15272" -->
</p>
<p>© Copyright Beman Dawes 2000</p>

<p>Distributed under the Boost Software License, Version 1.0. See
<a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a></p>

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