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diff --git a/doc/html/boost/process/std_in.html b/doc/html/boost/process/std_in.html new file mode 100644 index 0000000000..95e3e8ea9e --- /dev/null +++ b/doc/html/boost/process/std_in.html @@ -0,0 +1,203 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Global std_in</title> +<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> +<link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> +<link rel="up" href="../../process/reference.html#header.boost.process.io_hpp" title="Header <boost/process/io.hpp>"> +<link rel="prev" href="null.html" title="Global null"> +<link rel="next" href="std_out.html" title="Global std_out"> +</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="null.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../process/reference.html#header.boost.process.io_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="std_out.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="refentry"> +<a name="boost.process.std_in"></a><div class="titlepage"></div> +<div class="refnamediv"> +<h2><span class="refentrytitle">Global std_in</span></h2> +<p>boost::process::std_in</p> +</div> +<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> +<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../process/reference.html#header.boost.process.io_hpp" title="Header <boost/process/io.hpp>">boost/process/io.hpp</a>> + +</span><span class="emphasis"><em><span class="identifier">unspecified</span></em></span> std_in<span class="special">;</span></pre></div> +<div class="refsect1"> +<a name="idp433738496"></a><h2>Description</h2> +<p>This property allows to set the input stream for the child process.</p> +<div class="sect1"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="namespaceboost_1_1process_1stdin_details"></a>Details</h2></div></div></div> +<div class="toc"><dl class="toc"> +<dt><span class="sect2"><a href="std_in.html#namespaceboost_1_1process_1stdin_file">File Input</a></span></dt> +<dt><span class="sect2"><a href="std_in.html#namespaceboost_1_1process_1stdin_pipe">Pipe Input</a></span></dt> +<dt><span class="sect2"><a href="std_in.html#namespaceboost_1_1process_1stdin_async_pipe">Asynchronous Pipe Input</a></span></dt> +<dt><span class="sect2"><a href="std_in.html#namespaceboost_1_1process_1stdin_close">Close</a></span></dt> +<dt><span class="sect2"><a href="std_in.html#namespaceboost_1_1process_1stdin_null">Null</a></span></dt> +</dl></div> +<div class="sect2"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="namespaceboost_1_1process_1stdin_file"></a>File Input</h3></div></div></div> +<p>The file I/O simple redirects the stream to a file, for which the possible types are</p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"><p><code class="computeroutput">boost::filesystem::path</code></p></li> +<li class="listitem"><p><code class="computeroutput">std::basic_string<char_type></code></p></li> +<li class="listitem"><p><code class="computeroutput">const char_type*</code></p></li> +<li class="listitem"><p><code class="computeroutput">FILE*</code></p></li> +</ul></div> +<p> +</p> +<p>with <code class="computeroutput">char_type</code> being either <code class="computeroutput">char</code> or <code class="computeroutput">wchar_t</code>.</p> +<p>FILE* is explicitly added, so the process can easily redirect the output stream of the child to another output stream of the process. That is:</p> +<pre class="programlisting"><span class="identifier">system</span><span class="special">(</span><span class="string">"ls"</span><span class="special">,</span> <span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">stdin</span><span class="special">)</span><span class="special">;</span> +</pre> +<div class="warning"><table border="0" summary="Warning"> +<tr> +<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../../doc/src/images/warning.png"></td> +<th align="left">Warning</th> +</tr> +<tr><td align="left" valign="top"><p>If the launching and the child process use the input, this leads to undefined behaviour.</p></td></tr> +</table></div> +<p> +A syntax like <code class="computeroutput">system("ls", std_out > std::cerr)</code> is not possible, due to the C++ implementation not providing access to the handle.</p> +<p>The valid expressions for this property are</p> +<pre class="programlisting"><span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">file</span><span class="special">;</span> +<span class="identifier">std_in</span> <span class="special">=</span> <span class="identifier">file</span><span class="special">;</span> +</pre> +</div> +<div class="sect2"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="namespaceboost_1_1process_1stdin_pipe"></a>Pipe Input</h3></div></div></div> +<p>As explained in the corresponding section, the boost.process library provides a <a class="link" href="async_pipe.html" title="Class async_pipe">async_pipe</a> class which can be used to communicate with child processes.</p> +<div class="note"><table border="0" summary="Note"> +<tr> +<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../doc/src/images/note.png"></td> +<th align="left">Note</th> +</tr> +<tr><td align="left" valign="top"><p>Technically the <a class="link" href="async_pipe.html" title="Class async_pipe">async_pipe</a> works synchronous here, since no asio implementation is used by the library here. The async-operation will then however not end if the process is finished, since the pipe remains open. You can use the async_close function with on_exit to fix that.</p></td></tr> +</table></div> +<p> +Valid expressions with pipes are these:</p> +<pre class="programlisting"><span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">pipe</span><span class="special">;</span> +<span class="identifier">std_in</span> <span class="special">=</span> <span class="identifier">pipe</span><span class="special">;</span> +</pre> +<p>Where the valid types for <code class="computeroutput">pipe</code> are the following:</p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"><p><code class="computeroutput"><a class="link" href="basic_pipe.html" title="Class template basic_pipe">basic_pipe</a></code></p></li> +<li class="listitem"><p><code class="computeroutput"><a class="link" href="async_pipe.html" title="Class async_pipe">async_pipe</a></code></p></li> +<li class="listitem"><p><code class="computeroutput"><a class="link" href="basic_opstream.html" title="Class template basic_opstream">basic_opstream</a></code></p></li> +<li class="listitem"><p><code class="computeroutput"><a class="link" href="basic_pstream.html" title="Class template basic_pstream">basic_pstream</a></code></p></li> +</ul></div> +<p> +</p> +<p>Note that the pipe may also be used between several processes, like this:</p> +<pre class="programlisting"><span class="identifier">pipe</span> <span class="identifier">p</span><span class="special">;</span> +<span class="identifier">child</span> <span class="identifier">c1</span><span class="special">(</span><span class="string">"nm"</span><span class="special">,</span> <span class="string">"a.out"</span><span class="special">,</span> <span class="identifier">std_out</span><span class="special">></span><span class="identifier">p</span><span class="special">)</span><span class="special">;</span> +<span class="identifier">child</span> <span class="identifier">c2</span><span class="special">(</span><span class="string">"c++filt"</span><span class="special">,</span> <span class="identifier">std_in</span><span class="special"><</span><span class="identifier">p</span><span class="special">)</span><span class="special">;</span> +</pre> +</div> +<div class="sect2"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="namespaceboost_1_1process_1stdin_async_pipe"></a>Asynchronous Pipe Input</h3></div></div></div> +<p>Asynchronous Pipe I/O classifies communication which has automatically handling of the asynchronous operations by the process library. This means, that a pipe will be constructed, the async_read/-write will be automatically started, and that the end of the child process will also close the pipe.</p> +<p>Valid types for pipe I/O are the following:</p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"><p><code class="computeroutput">boost::asio::const_buffer</code> <a href="#ftn.idp433798448" class="footnote" name="idp433798448"><sup class="footnote">[8]</sup></a> </p></li> +<li class="listitem"><p><code class="computeroutput">boost::asio::mutable_buffer</code> <a href="#ftn.idp433800512" class="footnote" name="idp433800512"><sup class="footnote">[9]</sup></a> </p></li> +<li class="listitem"><p><code class="computeroutput">boost::asio::streambuf</code></p></li> +</ul></div> +<p> +</p> +<p>Valid expressions with pipes are these:</p> +<pre class="programlisting"><span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="identifier">std_in</span> <span class="special">=</span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="identifier">std_out</span> <span class="special">></span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="identifier">std_out</span> <span class="special">=</span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="identifier">std_err</span> <span class="special">></span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="identifier">std_err</span> <span class="special">=</span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="special">(</span><span class="identifier">std_out</span> <span class="special">&</span> <span class="identifier">std_err</span><span class="special">)</span> <span class="special">></span> <span class="identifier">buffer</span><span class="special">;</span> +<span class="special">(</span><span class="identifier">std_out</span> <span class="special">&</span> <span class="identifier">std_err</span><span class="special">)</span> <span class="special">=</span> <span class="identifier">buffer</span><span class="special">;</span> +</pre> +<div class="note"><table border="0" summary="Note"> +<tr> +<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../doc/src/images/note.png"></td> +<th align="left">Note</th> +</tr> +<tr><td align="left" valign="top"> +<p>It is also possible to get a future for std_in, by chaining another <code class="computeroutput">std::future<void></code> onto it, so you can wait for the input to be completed. It looks like this: </p> +<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">future</span><span class="special"><</span><span class="keyword">void</span><span class="special">></span> <span class="identifier">fut</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">io_service</span> <span class="identifier">ios</span><span class="special">;</span> +<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">data</span><span class="special">;</span> +<span class="identifier">child</span> <span class="identifier">c</span><span class="special">(</span><span class="string">"prog"</span><span class="special">,</span> <span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">buffer</span><span class="special">(</span><span class="identifier">data</span><span class="special">)</span> <span class="special">></span> <span class="identifier">fut</span><span class="special">,</span> <span class="identifier">ios</span><span class="special">)</span><span class="special">;</span> +<span class="identifier">fut</span><span class="special">.</span><span class="identifier">get</span><span class="special">(</span><span class="special">)</span><span class="special">;</span> +</pre> +<p><code class="computeroutput">boost::asio::buffer</code> is also available in the <code class="computeroutput">boost::process</code> namespace.</p> +</td></tr> +</table></div> +<p> +</p> +<div class="warning"><table border="0" summary="Warning"> +<tr> +<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../../doc/src/images/warning.png"></td> +<th align="left">Warning</th> +</tr> +<tr><td align="left" valign="top"><p>This feature requires <code class="computeroutput">boost/process/async.hpp</code> to be included and a reference to <code class="computeroutput">boost::asio::io_service</code> to be passed to the launching function.</p></td></tr> +</table></div> +<p> +</p> +</div> +<div class="sect2"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="namespaceboost_1_1process_1stdin_close"></a>Close</h3></div></div></div> +<p>The input stream can be closed, so it cannot be read from. This will lead to an error when attempted.</p> +<p>This can be achieved by the following syntax.</p> +<pre class="programlisting"><span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">close</span><span class="special">;</span> +<span class="identifier">std_in</span> <span class="special">=</span> <span class="identifier">close</span><span class="special">;</span> +<span class="identifier">std_in</span><span class="special">.</span><span class="identifier">close</span><span class="special">(</span><span class="special">)</span><span class="special">;</span> +</pre> +</div> +<div class="sect2"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="namespaceboost_1_1process_1stdin_null"></a>Null</h3></div></div></div> +<p>The input stream can be redirected to read from the null-device, which means that only <code class="computeroutput">EOF</code> is read.</p> +<p>The syntax to achieve that has the following variants:</p> +<pre class="programlisting"><span class="identifier">std_in</span> <span class="special"><</span> <span class="identifier">null</span><span class="special">;</span> +<span class="identifier">std_in</span> <span class="special">=</span> <span class="identifier">null</span><span class="special">;</span> +<span class="identifier">std_in</span><span class="special">.</span><span class="identifier">null</span><span class="special">(</span><span class="special">)</span><span class="special">;</span> +</pre> +<p> </p> +</div> +</div> +</div> +<div class="footnotes"> +<br><hr style="width:100; text-align:left;margin-left: 0"> +<div id="ftn.idp433798448" class="footnote"><p><a href="#idp433798448" class="para"><sup class="para">[8] </sup></a> Constructed with <code class="computeroutput">boost::asio::buffer</code></p></div> +<div id="ftn.idp433800512" class="footnote"><p><a href="#idp433800512" class="para"><sup class="para">[9] </sup></a> Constructed with <code class="computeroutput">boost::asio::buffer</code></p></div> +</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 © 2006-2012 Julio M. Merino Vidal, Ilya Sokolov, + Felipe Tanus, Jeff Flinn, Boris Schaeling<br>Copyright © 2016 Klemens D. Morgenstern<p> + Distributed under the Boost Software License, Version 1.0. (See accompanying + file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="null.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../process/reference.html#header.boost.process.io_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="std_out.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |