<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
<title>async_write (1 of 8 overloads)</title>
<link rel="stylesheet" href="../../../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.75.2">
<link rel="home" href="../../../index.html" title="Asio">
<link rel="up" href="../async_write.html" title="async_write">
<link rel="prev" href="../async_write.html" title="async_write">
<link rel="next" href="overload2.html" title="async_write (2 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="asio C++ library" width="250" height="60" src="../../../asio.png"></td></tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="../async_write.html"><img src="../../../prev.png" alt="Prev"></a><a accesskey="u" href="../async_write.html"><img src="../../../up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../home.png" alt="Home"></a><a accesskey="n" href="overload2.html"><img src="../../../next.png" alt="Next"></a>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="asio.reference.async_write.overload1"></a><a class="link" href="overload1.html" title="async_write (1 of 8 overloads)">async_write (1
        of 8 overloads)</a>
</h4></div></div></div>
<p>
          Start an asynchronous operation to write all of the supplied data to a
          stream.
        </p>
<pre class="programlisting">template&lt;
    typename <a class="link" href="../AsyncWriteStream.html" title="Buffer-oriented asynchronous write stream requirements">AsyncWriteStream</a>,
    typename <a class="link" href="../ConstBufferSequence.html" title="Constant buffer sequence requirements">ConstBufferSequence</a>,
    typename <a class="link" href="../WriteHandler.html" title="Write handler requirements">WriteHandler</a>&gt;
<a class="link" href="../asynchronous_operations.html#asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type"><span class="emphasis"><em>DEDUCED</em></span></a> async_write(
    AsyncWriteStream &amp; s,
    const ConstBufferSequence &amp; buffers,
    WriteHandler &amp;&amp; handler,
    typename enable_if&lt; is_const_buffer_sequence&lt; ConstBufferSequence &gt;::value &gt;::type *  = 0);
</pre>
<p>
          This function is used to asynchronously write a certain number of bytes
          of data to a stream. The function call always returns immediately. The
          asynchronous operation will continue until one of the following conditions
          is true:
        </p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
              All of the data in the supplied buffers has been written. That is,
              the bytes transferred is equal to the sum of the buffer sizes.
            </li>
<li class="listitem">
              An error occurred.
            </li>
</ul></div>
<p>
          This operation is implemented in terms of zero or more calls to the stream's
          async_write_some function, and is known as a <span class="emphasis"><em>composed operation</em></span>.
          The program must ensure that the stream performs no other write operations
          (such as async_write, the stream's async_write_some function, or any other
          composed operations that perform writes) until this operation completes.
        </p>
<h6>
<a name="asio.reference.async_write.overload1.h0"></a>
          <span><a name="asio.reference.async_write.overload1.parameters"></a></span><a class="link" href="overload1.html#asio.reference.async_write.overload1.parameters">Parameters</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">s</span></dt>
<dd><p>
                The stream to which the data is to be written. The type must support
                the AsyncWriteStream concept.
              </p></dd>
<dt><span class="term">buffers</span></dt>
<dd><p>
                One or more buffers containing the data to be written. Although the
                buffers object may be copied as necessary, ownership of the underlying
                memory blocks is retained by the caller, which must guarantee that
                they remain valid until the handler is called.
              </p></dd>
<dt><span class="term">handler</span></dt>
<dd>
<p>
                The handler to be called when the write operation completes. Copies
                will be made of the handler as required. The function signature of
                the handler must be:
</p>
<pre class="programlisting">void handler(
  const asio::error_code&amp; error, // Result of operation.

  std::size_t bytes_transferred           // Number of bytes written from the
                                          // buffers. If an error occurred,
                                          // this will be less than the sum
                                          // of the buffer sizes.
);
</pre>
<p>
                Regardless of whether the asynchronous operation completes immediately
                or not, the handler will not be invoked from within this function.
                On immediate completion, invocation of the handler will be performed
                in a manner equivalent to using <a class="link" href="../post.html" title="post"><code class="computeroutput">post</code></a>.
              </p>
</dd>
</dl>
</div>
<h6>
<a name="asio.reference.async_write.overload1.h1"></a>
          <span><a name="asio.reference.async_write.overload1.example"></a></span><a class="link" href="overload1.html#asio.reference.async_write.overload1.example">Example</a>
        </h6>
<p>
          To write a single data buffer use the <a class="link" href="../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
          function as follows:
        </p>
<pre class="programlisting">asio::async_write(s, asio::buffer(data, size), handler);
</pre>
<p>
          See the <a class="link" href="../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
          documentation for information on writing multiple buffers in one go, and
          how to use it with arrays, boost::array or std::vector.
        </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 &#169; 2003-2019 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="../async_write.html"><img src="../../../prev.png" alt="Prev"></a><a accesskey="u" href="../async_write.html"><img src="../../../up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../home.png" alt="Home"></a><a accesskey="n" href="overload2.html"><img src="../../../next.png" alt="Next"></a>
</div>
</body>
</html>
