<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>transfer_at_least</title> <link rel="stylesheet" href="../../boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.75.2"> <link rel="home" href="../../boost_asio.html" title="Boost.Asio"> <link rel="up" href="../reference.html" title="Reference"> <link rel="prev" href="transfer_all.html" title="transfer_all"> <link rel="next" href="use_service.html" title="use_service"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr> <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> <td align="center"><a href="../../../../index.html">Home</a></td> <td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td> <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> <td align="center"><a 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operation should continue until a minimum number of bytes has been transferred, or until an error occurs. </p> <pre class="programlisting"><span class="identifier">unspecified</span> <span class="identifier">transfer_at_least</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">minimum</span><span class="special">);</span> </pre> <p> This function is used to create an object, of unspecified type, that meets CompletionCondition requirements. </p> <a name="boost_asio.reference.transfer_at_least.example"></a><h5> <a name="id1135343"></a> <a class="link" href="transfer_at_least.html#boost_asio.reference.transfer_at_least.example">Example</a> </h5> <p> Reading until a buffer is full or contains at least 64 bytes: </p> <pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">array</span><span class="special"><</span><span class="keyword">char</span><span class="special">,</span> <span class="number">128</span><span class="special">></span> <span class="identifier">buf</span><span class="special">;</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span> <span class="identifier">ec</span><span class="special">;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">n</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">read</span><span class="special">(</span> <span class="identifier">sock</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer</span><span class="special">(</span><span class="identifier">buf</span><span class="special">),</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">transfer_at_least</span><span class="special">(</span><span class="number">64</span><span class="special">),</span> <span class="identifier">ec</span><span class="special">);</span> <span class="keyword">if</span> <span class="special">(</span><span class="identifier">ec</span><span class="special">)</span> <span class="special">{</span> <span class="comment">// An error occurred. </span><span class="special">}</span> <span class="keyword">else</span> <span class="special">{</span> <span class="comment">// n >= 64 && n <= 128 </span><span class="special">}</span> </pre> <a name="boost_asio.reference.transfer_at_least.requirements"></a><h5> <a name="id1135654"></a> <a class="link" href="transfer_at_least.html#boost_asio.reference.transfer_at_least.requirements">Requirements</a> </h5> <p> <span class="bold"><strong>Header: </strong></span><code class="literal">boost/asio/completion_condition.hpp</code> </p> <p> <span class="bold"><strong>Convenience header: </strong></span><code class="literal">boost/asio.hpp</code> </p> </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 © 2003 - 2010 Christopher M. Kohlhoff<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> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="transfer_all.html"><img src="../../../../doc/html/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../doc/html/images/up.png" alt="Up"></a><a accesskey="h" href="../../boost_asio.html"><img src="../../../../doc/html/images/home.png" alt="Home"></a><a accesskey="n" href="use_service.html"><img src="../../../../doc/html/images/next.png" alt="Next"></a> </div> </body> </html>