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<li><a class="reference internal" href="#"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pipes</span></code> — Interface to shell pipelines</a><ul>
<li><a class="reference internal" href="#template-objects">Template Objects</a></li>
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<section id="module-pipes">
<span id="pipes-interface-to-shell-pipelines"></span><h1><a class="reference internal" href="#module-pipes" title="pipes: A Python interface to Unix shell pipelines. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pipes</span></code></a> — Interface to shell pipelines<a class="headerlink" href="#module-pipes" title="Permalink to this headline">¶</a></h1>
<p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.10/Lib/pipes.py">Lib/pipes.py</a></p>
<div class="deprecated">
<p><span class="versionmodified deprecated">Deprecated since version 3.11: </span>The <a class="reference internal" href="#module-pipes" title="pipes: A Python interface to Unix shell pipelines. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pipes</span></code></a> module is deprecated
(see <span class="target" id="index-0"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0594#pipes"><strong>PEP 594</strong></a> for details).
Please use the <a class="reference internal" href="subprocess.html#module-subprocess" title="subprocess: Subprocess management."><code class="xref py py-mod docutils literal notranslate"><span class="pre">subprocess</span></code></a> module instead.</p>
</div>
<hr class="docutils" />
<p>The <a class="reference internal" href="#module-pipes" title="pipes: A Python interface to Unix shell pipelines. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pipes</span></code></a> module defines a class to abstract the concept of a <em>pipeline</em>
— a sequence of converters from one file to another.</p>
<p>Because the module uses <strong class="program">/bin/sh</strong> command lines, a POSIX or compatible
shell for <a class="reference internal" href="os.html#os.system" title="os.system"><code class="xref py py-func docutils literal notranslate"><span class="pre">os.system()</span></code></a> and <a class="reference internal" href="os.html#os.popen" title="os.popen"><code class="xref py py-func docutils literal notranslate"><span class="pre">os.popen()</span></code></a> is required.</p>
<p class="availability"><a class="reference internal" href="intro.html#availability"><span class="std std-ref">Availability</span></a>: Unix. Not available on VxWorks.</p>
<p>The <a class="reference internal" href="#module-pipes" title="pipes: A Python interface to Unix shell pipelines. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pipes</span></code></a> module defines the following class:</p>
<dl class="py class">
<dt class="sig sig-object py" id="pipes.Template">
<em class="property"><span class="pre">class</span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">pipes.</span></span><span class="sig-name descname"><span class="pre">Template</span></span><a class="headerlink" href="#pipes.Template" title="Permalink to this definition">¶</a></dt>
<dd><p>An abstraction of a pipeline.</p>
</dd></dl>
<p>Example:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">pipes</span>
<span class="gp">>>> </span><span class="n">t</span> <span class="o">=</span> <span class="n">pipes</span><span class="o">.</span><span class="n">Template</span><span class="p">()</span>
<span class="gp">>>> </span><span class="n">t</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="s1">'tr a-z A-Z'</span><span class="p">,</span> <span class="s1">'--'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">f</span> <span class="o">=</span> <span class="n">t</span><span class="o">.</span><span class="n">open</span><span class="p">(</span><span class="s1">'pipefile'</span><span class="p">,</span> <span class="s1">'w'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">f</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s1">'hello world'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">f</span><span class="o">.</span><span class="n">close</span><span class="p">()</span>
<span class="gp">>>> </span><span class="nb">open</span><span class="p">(</span><span class="s1">'pipefile'</span><span class="p">)</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
<span class="go">'HELLO WORLD'</span>
</pre></div>
</div>
<section id="template-objects">
<span id="id1"></span><h2>Template Objects<a class="headerlink" href="#template-objects" title="Permalink to this headline">¶</a></h2>
<p>Template objects following methods:</p>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.reset">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">reset</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.reset" title="Permalink to this definition">¶</a></dt>
<dd><p>Restore a pipeline template to its initial state.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.clone">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">clone</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.clone" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a new, equivalent, pipeline template.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.debug">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">debug</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">flag</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.debug" title="Permalink to this definition">¶</a></dt>
<dd><p>If <em>flag</em> is true, turn debugging on. Otherwise, turn debugging off. When
debugging is on, commands to be executed are printed, and the shell is given
<code class="docutils literal notranslate"><span class="pre">set</span> <span class="pre">-x</span></code> command to be more verbose.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.append">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">append</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">cmd</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">kind</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.append" title="Permalink to this definition">¶</a></dt>
<dd><p>Append a new action at the end. The <em>cmd</em> variable must be a valid bourne shell
command. The <em>kind</em> variable consists of two letters.</p>
<p>The first letter can be either of <code class="docutils literal notranslate"><span class="pre">'-'</span></code> (which means the command reads its
standard input), <code class="docutils literal notranslate"><span class="pre">'f'</span></code> (which means the commands reads a given file on the
command line) or <code class="docutils literal notranslate"><span class="pre">'.'</span></code> (which means the commands reads no input, and hence
must be first.)</p>
<p>Similarly, the second letter can be either of <code class="docutils literal notranslate"><span class="pre">'-'</span></code> (which means the command
writes to standard output), <code class="docutils literal notranslate"><span class="pre">'f'</span></code> (which means the command writes a file on
the command line) or <code class="docutils literal notranslate"><span class="pre">'.'</span></code> (which means the command does not write anything,
and hence must be last.)</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.prepend">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">prepend</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">cmd</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">kind</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.prepend" title="Permalink to this definition">¶</a></dt>
<dd><p>Add a new action at the beginning. See <a class="reference internal" href="#pipes.Template.append" title="pipes.Template.append"><code class="xref py py-meth docutils literal notranslate"><span class="pre">append()</span></code></a> for explanations of the
arguments.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.open">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">open</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">file</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">mode</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.open" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a file-like object, open to <em>file</em>, but read from or written to by the
pipeline. Note that only one of <code class="docutils literal notranslate"><span class="pre">'r'</span></code>, <code class="docutils literal notranslate"><span class="pre">'w'</span></code> may be given.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="pipes.Template.copy">
<span class="sig-prename descclassname"><span class="pre">Template.</span></span><span class="sig-name descname"><span class="pre">copy</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">infile</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">outfile</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#pipes.Template.copy" title="Permalink to this definition">¶</a></dt>
<dd><p>Copy <em>infile</em> to <em>outfile</em> through the pipe.</p>
</dd></dl>
</section>
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