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| <div class="titlepage"><div><div><h2 class="title" style="clear: both"> |
| <a name="boost_integer.cstdint"></a><a class="link" href="cstdint.html" title="Standard Integer Types"> Standard Integer Types</a> |
| </h2></div></div></div> |
| <div class="toc"><dl> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.overview">Overview</a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.rationale"> Rationale</a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.ce"> <span class="emphasis"><em>Caveat emptor</em></span></a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.exact_width_integer_types">Exact-width |
| integer types</a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.minimum_width_integer_types">Minimum-width |
| integer types</a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.fastest_minimum_width_integer_types">Fastest |
| minimum-width integer types</a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.greatest_width_integer_types">Greatest-width |
| integer types</a></span></dt> |
| <dt><span class="section"><a href="cstdint.html#boost_integer.cstdint.integer_constant_macros">Integer |
| Constant Macros</a></span></dt> |
| </dl></div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.overview"></a><a class="link" href="cstdint.html#boost_integer.cstdint.overview" title="Overview">Overview</a> |
| </h3></div></div></div> |
| <p> |
| The header <code class="literal"><a href="../../../../../boost/cstdint.hpp" target="_top"><boost/cstdint.hpp></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 for these types are based on the ISO/IEC 9899:1999 C Language |
| standard header <stdint.h>. The 64-bit types required by the C standard |
| are <span class="emphasis"><em>not required</em></span> in the boost header, and may not be |
| supplied for all platforms/compilers, because <code class="literal">long long</code> |
| is not [yet] included in the C++ standard. |
| </p> |
| <p> |
| See <a href="../../../test/cstdint_test.cpp" target="_top">cstdint_test.cpp</a> for |
| a test program. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.rationale"></a><a class="link" href="cstdint.html#boost_integer.cstdint.rationale" title="Rationale"> Rationale</a> |
| </h3></div></div></div> |
| <p> |
| The organization of the Boost.Integer headers and classes is designed to |
| take advantage of <stdint.h> types from the 1999 C standard without |
| causing undefined behavior in terms of the 1998 C++ standard. The header |
| <boost/cstdint.hpp> makes the standard integer types safely available |
| in namespace <code class="literal">boost</code> without placing any names in namespace |
| <code class="literal">std</code>. The intension is to complement rather than compete |
| with the C++ Standard Library. Should some future C++ standard include <stdint.h> |
| and <cstdint>, then <boost/cstdint.hpp> will continue to function, |
| but will become redundant and may be safely deprecated. |
| </p> |
| <p> |
| Because these are boost headers, their names conform to boost header naming |
| conventions rather than C++ Standard Library header naming conventions. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.ce"></a><a class="link" href="cstdint.html#boost_integer.cstdint.ce" title="Caveat emptor"> <span class="emphasis"><em>Caveat emptor</em></span></a> |
| </h3></div></div></div> |
| <p> |
| As an implementation artifact, certain C <limits.h> macro names may |
| possibly be visible to users of <boost/cstdint.hpp>. Don't use these |
| macros; they are not part of any Boost-specified interface. Use <code class="literal">boost::integer_traits<></code> |
| or <code class="literal">std::numeric_limits<></code> instead. |
| </p> |
| <p> |
| As another implementation artifact, certain C <stdint.h> typedef names |
| may possibly be visible in the global namespace to users of <boost/cstdint.hpp>. |
| Don't use these names, they are not part of any Boost-specified interface. |
| Use the respective names in namespace <code class="literal">boost</code> instead. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.exact_width_integer_types"></a><a class="link" href="cstdint.html#boost_integer.cstdint.exact_width_integer_types" title="Exact-width integer types">Exact-width |
| integer types</a> |
| </h3></div></div></div> |
| <p> |
| The typedef <code class="literal">int#_t</code>, with # replaced by the width, designates |
| a signed integer type of exactly # bits; for example <code class="literal">int8_t</code> |
| denotes an 8-bit signed integer type. Similarly, the typedef <code class="literal">uint#_t</code> |
| designates an unsigned integer type of exactly # bits. |
| </p> |
| <p> |
| These types are optional. However, if a platform supports integer types with |
| widths of 8, 16, 32, 64, or any combination thereof, then <boost/cstdint.hpp> |
| does provide the corresponding typedefs. |
| </p> |
| <p> |
| 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>. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.minimum_width_integer_types"></a><a class="link" href="cstdint.html#boost_integer.cstdint.minimum_width_integer_types" title="Minimum-width integer types">Minimum-width |
| integer types</a> |
| </h3></div></div></div> |
| <p> |
| The typedef <code class="literal">int_least#_t</code>, with # replaced by the width, |
| 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 class="literal">int_least32_t</code> denotes the smallest signed integer |
| type with a width of at least 32 bits. Similarly, the typedef name <code class="literal">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> |
| The following minimum-width integer types are provided for all platforms: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <code class="literal">int_least8_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">int_least16_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">int_least32_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_least8_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_least16_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_least32_t</code> |
| </li> |
| </ul></div> |
| <p> |
| The following types are available only if, after including <boost/cstdint.hpp>, |
| the macro BOOST_NO_INT64_T is not defined: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <code class="literal">int_least64_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_least64_t</code> |
| </li> |
| </ul></div> |
| <p> |
| All other minimum-width integer types are optional. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.fastest_minimum_width_integer_types"></a><a class="link" href="cstdint.html#boost_integer.cstdint.fastest_minimum_width_integer_types" title="Fastest minimum-width integer types">Fastest |
| minimum-width integer types</a> |
| </h3></div></div></div> |
| <p> |
| The typedef <code class="literal">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 class="literal">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. In any |
| case, however, they satisfy the signedness and width requirements. |
| </p> |
| <p> |
| The following fastest minimum-width integer types are provided for all platforms: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <code class="literal">int_fast8_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">int_fast16_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">int_fast32_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_fast8_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_fast16_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_fast32_t</code> |
| </li> |
| </ul></div> |
| <p> |
| The following types are available only if, after including <boost/cstdint.hpp>, |
| the macro BOOST_NO_INT64_T is not defined: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <code class="literal">int_fast64_t</code> |
| </li> |
| <li class="listitem"> |
| <code class="literal">uint_fast64_t</code> |
| </li> |
| </ul></div> |
| <p> |
| All other fastest minimum-width integer types are optional. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.greatest_width_integer_types"></a><a class="link" href="cstdint.html#boost_integer.cstdint.greatest_width_integer_types" title="Greatest-width integer types">Greatest-width |
| integer types</a> |
| </h3></div></div></div> |
| <p> |
| The typedef <code class="literal">intmax_t </code>designates a signed integer type |
| capable of representing any value of any signed integer type. |
| </p> |
| <p> |
| The typedef <code class="literal">uintmax_t</code> designates an unsigned integer type |
| capable of representing any value of any unsigned integer type. |
| </p> |
| <p> |
| These types are provided for all platforms. |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_integer.cstdint.integer_constant_macros"></a><a class="link" href="cstdint.html#boost_integer.cstdint.integer_constant_macros" title="Integer Constant Macros">Integer |
| Constant Macros</a> |
| </h3></div></div></div> |
| <p> |
| The following macros are always defined after inclusion of this header, these |
| allow integer constants of at least the specified width to be declared: INT8_C, |
| UINT8_C, INT16_C, UINT16_C, INT32_C, UINT32_C, INTMAX_C, UINTMAX_C. |
| </p> |
| <p> |
| The macros INT64_C and UINT64_C are also defined if the the macro BOOST_NO_INT64_T |
| is not defined. |
| </p> |
| <p> |
| The C99 macro __STDC_CONSTANT_MACROS is also defined as an artifact of the |
| implementation. |
| </p> |
| <p> |
| For example: |
| </p> |
| <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> |
| |
| <span class="comment">// Here the constant 0x1FFFFFFFF has the correct suffix applied: |
| </span><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> |
| </pre> |
| </div> |
| </div> |
| <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> |
| <td align="left"></td> |
| <td align="right"><div class="copyright-footer">Copyright © 2001 -2009 Beman Dawes, Daryle Walker, Gennaro Prota, |
| John Maddock<p> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 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>) |
| </p> |
| </div></td> |
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