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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
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<a name="boost_config.cstdint"></a><a class="link" href="cstdint.html" title="Standard Integer Types">Standard Integer Types</a>
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</h2></div></div></div>
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<div class="toc"><dl class="toc">
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.overview">Overview</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.rationale">Rationale</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.ce"><span class="emphasis"><em>Caveat emptor</em></span></a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.exact_width_integer_types">Exact-width
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integer types</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.minimum_width_integer_types">Minimum-width
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integer types</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.fastest_minimum_width_integer_types">Fastest
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minimum-width integer types</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.greatest_width_integer_types">Greatest-width
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integer types</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.integer_constant_macros">Integer
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Constant Macros</a></span></dt>
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<dt><span class="section"><a href="cstdint.html#boost_config.cstdint.intptr">Integers for Storing Pointers</a></span></dt>
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</dl></div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.overview"></a><a class="link" href="cstdint.html#boost_config.cstdint.overview" title="Overview">Overview</a>
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</h3></div></div></div>
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<p>
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The header <code class="literal"><a href="../../../../../boost/cstdint.hpp" target="_top"><boost/cstdint.hpp></a></code>
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provides the typedef's useful for writing portable code that requires certain
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integer widths. All typedef's are in namespace boost.
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</p>
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<p>
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The specifications for these types are based on the ISO/IEC 9899:1999 C Language
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standard header <stdint.h>. The 64-bit types required by the C standard
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are <span class="emphasis"><em>not required</em></span> in the boost header, and may not be
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supplied for all platforms/compilers, because <code class="literal">long long</code>
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is not [yet] included in the C++ standard.
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</p>
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<p>
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See <a href="../../../test/cstdint_test.cpp" target="_top">cstdint_test.cpp</a> for
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a test program.
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</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.rationale"></a><a class="link" href="cstdint.html#boost_config.cstdint.rationale" title="Rationale">Rationale</a>
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</h3></div></div></div>
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<p>
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The organization of the Boost.Integer headers and classes is designed to
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take advantage of <stdint.h> types from the 1999 C standard without
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causing undefined behavior in terms of the 1998 C++ standard. The header
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<boost/cstdint.hpp> makes the standard integer types safely available
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in namespace <code class="literal">boost</code> without placing any names in namespace
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<code class="literal">std</code>. The intension is to complement rather than compete
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with the C++ Standard Library. Should some future C++ standard include <stdint.h>
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and <cstdint>, then <boost/cstdint.hpp> will continue to function,
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but will become redundant and may be safely deprecated.
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</p>
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<p>
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Because these are boost headers, their names conform to boost header naming
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conventions rather than C++ Standard Library header naming conventions.
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</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.ce"></a><a class="link" href="cstdint.html#boost_config.cstdint.ce" title="Caveat emptor"><span class="emphasis"><em>Caveat emptor</em></span></a>
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</h3></div></div></div>
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<p>
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As an implementation artifact, certain C <limits.h> macro names may
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possibly be visible to users of <boost/cstdint.hpp>. Don't use these
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macros; they are not part of any Boost-specified interface. Use <code class="literal">boost::integer_traits<></code>
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or <code class="literal">std::numeric_limits<></code> instead.
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</p>
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<p>
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As another implementation artifact, certain C <stdint.h> typedef names
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may possibly be visible in the global namespace to users of <boost/cstdint.hpp>.
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Don't use these names, they are not part of any Boost-specified interface.
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Use the respective names in namespace <code class="literal">boost</code> instead.
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</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.exact_width_integer_types"></a><a class="link" href="cstdint.html#boost_config.cstdint.exact_width_integer_types" title="Exact-width integer types">Exact-width
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integer types</a>
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</h3></div></div></div>
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<p>
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The typedef <code class="literal">int#_t</code>, with # replaced by the width, designates
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a signed integer type of exactly # bits; for example <code class="literal">int8_t</code>
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denotes an 8-bit signed integer type. Similarly, the typedef <code class="literal">uint#_t</code>
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designates an unsigned integer type of exactly # bits.
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</p>
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<p>
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These types are optional. However, if a platform supports integer types with
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widths of 8, 16, 32, 64, or any combination thereof, then <boost/cstdint.hpp>
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does provide the corresponding typedefs.
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</p>
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<p>
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The absence of int64_t and uint64_t is indicated by the macro <code class="computeroutput"><span class="identifier">BOOST_NO_INT64_T</span></code>.
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</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.minimum_width_integer_types"></a><a class="link" href="cstdint.html#boost_config.cstdint.minimum_width_integer_types" title="Minimum-width integer types">Minimum-width
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integer types</a>
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</h3></div></div></div>
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<p>
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The typedef <code class="literal">int_least#_t</code>, with # replaced by the width,
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designates a signed integer type with a width of at least # bits, such that
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no signed integer type with lesser size has at least the specified width.
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Thus, <code class="literal">int_least32_t</code> denotes the smallest signed integer
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type with a width of at least 32 bits. Similarly, the typedef name <code class="literal">uint_least#_t</code>
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designates an unsigned integer type with a width of at least # bits, such
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that no unsigned integer type with lesser size has at least the specified
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width.
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</p>
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<p>
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The following minimum-width integer types are provided for all platforms:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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<code class="literal">int_least8_t</code>
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</li>
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<li class="listitem">
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<code class="literal">int_least16_t</code>
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</li>
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<li class="listitem">
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<code class="literal">int_least32_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_least8_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_least16_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_least32_t</code>
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</li>
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</ul></div>
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<p>
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The following types are available only if, after including <boost/cstdint.hpp>,
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the macro BOOST_NO_INT64_T is not defined:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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<code class="literal">int_least64_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_least64_t</code>
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</li>
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</ul></div>
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<p>
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All other minimum-width integer types are optional.
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</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.fastest_minimum_width_integer_types"></a><a class="link" href="cstdint.html#boost_config.cstdint.fastest_minimum_width_integer_types" title="Fastest minimum-width integer types">Fastest
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minimum-width integer types</a>
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</h3></div></div></div>
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<p>
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The typedef <code class="literal">int_fast#_t</code>, with # replaced by the width,
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designates the fastest signed integer type with a width of at least # bits.
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Similarly, the typedef name <code class="literal">uint_fast#_t</code> designates the
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fastest unsigned integer type with a width of at least # bits.
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</p>
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<p>
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There is no guarantee that these types are fastest for all purposes. In any
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case, however, they satisfy the signedness and width requirements.
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</p>
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<p>
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The following fastest minimum-width integer types are provided for all platforms:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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<code class="literal">int_fast8_t</code>
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</li>
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<li class="listitem">
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<code class="literal">int_fast16_t</code>
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</li>
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<li class="listitem">
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<code class="literal">int_fast32_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_fast8_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_fast16_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_fast32_t</code>
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</li>
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</ul></div>
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<p>
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The following types are available only if, after including <boost/cstdint.hpp>,
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the macro BOOST_NO_INT64_T is not defined:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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<code class="literal">int_fast64_t</code>
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</li>
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<li class="listitem">
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<code class="literal">uint_fast64_t</code>
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</li>
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</ul></div>
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<p>
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All other fastest minimum-width integer types are optional.
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</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.greatest_width_integer_types"></a><a class="link" href="cstdint.html#boost_config.cstdint.greatest_width_integer_types" title="Greatest-width integer types">Greatest-width
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integer types</a>
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</h3></div></div></div>
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<p>
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The typedef <code class="literal">intmax_t </code>designates a signed integer type
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capable of representing any value of any signed integer type.
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</p>
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<p>
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The typedef <code class="literal">uintmax_t</code> designates an unsigned integer type
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capable of representing any value of any unsigned integer type.
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</p>
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<p>
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These types are provided for all platforms.
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</p>
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</div>
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<div class="section">
|
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<div class="titlepage"><div><div><h3 class="title">
|
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<a name="boost_config.cstdint.integer_constant_macros"></a><a class="link" href="cstdint.html#boost_config.cstdint.integer_constant_macros" title="Integer Constant Macros">Integer
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Constant Macros</a>
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</h3></div></div></div>
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<p>
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The following macros are always defined after inclusion of this header, these
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allow integer constants of at least the specified width to be declared: INT8_C,
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UINT8_C, INT16_C, UINT16_C, INT32_C, UINT32_C, INTMAX_C, UINTMAX_C.
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</p>
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<p>
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The macros INT64_C and UINT64_C are also defined if the the macro BOOST_NO_INT64_T
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is not defined.
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</p>
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<p>
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The C99 macro __STDC_CONSTANT_MACROS is also defined as an artifact of the
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implementation.
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</p>
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<p>
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For example:
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</p>
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<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">cstdint</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
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<span class="comment">// Here the constant 0x1FFFFFFFF has the correct suffix applied:</span>
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<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint64_t</span> <span class="identifier">c</span> <span class="special">=</span> <span class="identifier">INT64_C</span><span class="special">(</span><span class="number">0</span><span class="identifier">x1FFFFFFFF</span><span class="special">);</span>
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</pre>
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</div>
|
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_config.cstdint.intptr"></a><a class="link" href="cstdint.html#boost_config.cstdint.intptr" title="Integers for Storing Pointers">Integers for Storing Pointers</a>
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</h3></div></div></div>
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<p>
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The typedefs <code class="literal">intptr_t</code> and <code class="literal">uintptr_t</code>
|
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defined signed and unsigned integers respectively each capable of storing
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a pointer. The macro <code class="literal">BOOST_HAS_INTPTR_T</code> is set when these
|
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types are available.
|
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</p>
|
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</div>
|
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</div>
|
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<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
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<td align="left"></td>
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<td align="right"><div class="copyright-footer">Copyright © 2001-2007 Beman Dawes, Vesa Karvonen, John
|
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Maddock<p>
|
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Distributed under the Boost Software License, Version 1.0. (See accompanying
|
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file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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</p>
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</div></td>
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</tr></table>
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