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diff --git a/doc/html/boost_asio/reference/read_at/overload4.html b/doc/html/boost_asio/reference/read_at/overload4.html new file mode 100755 index 0000000000..fd0ae46af6 --- /dev/null +++ b/doc/html/boost_asio/reference/read_at/overload4.html @@ -0,0 +1,133 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>read_at (4 of 8 overloads)</title> +<link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<link rel="home" href="../../../boost_asio.html" title="Boost.Asio"> +<link rel="up" href="../read_at.html" title="read_at"> +<link rel="prev" href="overload3.html" title="read_at (3 of 8 overloads)"> +<link rel="next" href="overload5.html" title="read_at (5 of 8 overloads)"> +</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 href="http://www.boost.org/users/faq.html">FAQ</a></td> +<td align="center"><a href="../../../../../more/index.htm">More</a></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="overload3.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../read_at.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../boost_asio.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload5.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h4 class="title"> +<a name="boost_asio.reference.read_at.overload4"></a><a class="link" href="overload4.html" title="read_at (4 of 8 overloads)">read_at (4 + of 8 overloads)</a> +</h4></div></div></div> +<p> + Attempt to read a certain amount of data at the specified offset before + returning. + </p> +<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> + <span class="keyword">typename</span> <a class="link" href="../SyncRandomAccessReadDevice.html" title="Buffer-oriented synchronous random-access read device requirements">SyncRandomAccessReadDevice</a><span class="special">,</span> + <span class="keyword">typename</span> <a class="link" href="../MutableBufferSequence.html" title="Mutable buffer sequence requirements">MutableBufferSequence</a><span class="special">,</span> + <span class="keyword">typename</span> <span class="identifier">CompletionCondition</span><span class="special">></span> +<span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">read_at</span><span class="special">(</span> + <span class="identifier">SyncRandomAccessReadDevice</span> <span class="special">&</span> <span class="identifier">d</span><span class="special">,</span> + <span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint64_t</span> <span class="identifier">offset</span><span class="special">,</span> + <span class="keyword">const</span> <span class="identifier">MutableBufferSequence</span> <span class="special">&</span> <span class="identifier">buffers</span><span class="special">,</span> + <span class="identifier">CompletionCondition</span> <span class="identifier">completion_condition</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="special">&</span> <span class="identifier">ec</span><span class="special">);</span> +</pre> +<p> + This function is used to read a certain number of bytes of data from a + random access device at the specified offset. The call will block until + one of the following conditions is true: + </p> +<div class="itemizedlist"><ul class="itemizedlist" type="disc"> +<li class="listitem"> + The supplied buffers are full. That is, the bytes transferred is equal + to the sum of the buffer sizes. + </li> +<li class="listitem"> + The completion_condition function object returns 0. + </li> +</ul></div> +<p> + This operation is implemented in terms of zero or more calls to the device's + read_some_at function. + </p> +<h6> +<a name="boost_asio.reference.read_at.overload4.h0"></a> + <span><a name="boost_asio.reference.read_at.overload4.parameters"></a></span><a class="link" href="overload4.html#boost_asio.reference.read_at.overload4.parameters">Parameters</a> + </h6> +<div class="variablelist"> +<p class="title"><b></b></p> +<dl> +<dt><span class="term">d</span></dt> +<dd><p> + The device from which the data is to be read. The type must support + the SyncRandomAccessReadDevice concept. + </p></dd> +<dt><span class="term">offset</span></dt> +<dd><p> + The offset at which the data will be read. + </p></dd> +<dt><span class="term">buffers</span></dt> +<dd><p> + One or more buffers into which the data will be read. The sum of + the buffer sizes indicates the maximum number of bytes to read from + the device. + </p></dd> +<dt><span class="term">completion_condition</span></dt> +<dd> +<p> + The function object to be called to determine whether the read operation + is complete. The signature of the function object must be: +</p> +<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">completion_condition</span><span class="special">(</span> + <span class="comment">// Result of latest read_some_at operation.</span> + <span class="keyword">const</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="special">&</span> <span class="identifier">error</span><span class="special">,</span> + + <span class="comment">// Number of bytes transferred so far.</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes_transferred</span> +<span class="special">);</span> +</pre> +<p> + A return value of 0 indicates that the read operation is complete. + A non-zero return value indicates the maximum number of bytes to + be read on the next call to the device's read_some_at function. + </p> +</dd> +<dt><span class="term">ec</span></dt> +<dd><p> + Set to indicate what error occurred, if any. + </p></dd> +</dl> +</div> +<h6> +<a name="boost_asio.reference.read_at.overload4.h1"></a> + <span><a name="boost_asio.reference.read_at.overload4.return_value"></a></span><a class="link" href="overload4.html#boost_asio.reference.read_at.overload4.return_value">Return Value</a> + </h6> +<p> + The number of bytes read. If an error occurs, returns the total number + of bytes successfully transferred prior to the error. + </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 © 2003-2012 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="overload3.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../read_at.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../boost_asio.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload5.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |