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<div class="language_switcher_placeholder"></div>166 <div class="version_switcher_placeholder"></div>167 </li>168 <li>169 170 </li>171 <li id="cpython-language-and-version">172 <a href="../index.html">3.15.0a6 Documentation</a> »173 </li>174 175 <li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> »</li>176 <li class="nav-item nav-item-2"><a href="cmdlinelibs.html" accesskey="U">Command-line interface libraries</a> »</li>177 <li class="nav-item nav-item-this"><a href=""><code class="xref py py-mod docutils literal notranslate"><span class="pre">fileinput</span></code> — Iterate over lines from multiple input streams</a></li>178 <li class="right">179 180 181 <div class="inline-search" role="search">182 <form class="inline-search" action="../search.html" method="get">183 <input placeholder="Quick search" aria-label="Quick search" type="search" name="q" id="search-box">184 <input type="submit" value="Go">185 </form>186 </div>187 |188 </li>189 <li class="right">190<label class="theme-selector-label">191 Theme192 <select class="theme-selector" oninput="activateTheme(this.value)">193 <option value="auto" selected>Auto</option>194 <option value="light">Light</option>195 <option value="dark">Dark</option>196 </select>197</label> |</li>198 199 </ul>200 </div> 201 202 <div class="document">203 <div class="documentwrapper">204 <div class="bodywrapper">205 <div class="body" role="main">206 207 <section id="module-fileinput">208<span id="fileinput-iterate-over-lines-from-multiple-input-streams"></span><h1><code class="xref py py-mod docutils literal notranslate"><span class="pre">fileinput</span></code> — Iterate over lines from multiple input streams<a class="headerlink" href="#module-fileinput" title="Link to this heading">¶</a></h1>209<p><strong>Source code:</strong> <a class="extlink-source reference external" href="https://github.com/python/cpython/tree/main/Lib/fileinput.py">Lib/fileinput.py</a></p>210<hr class="docutils" />211<p>This module implements a helper class and functions to quickly write a212loop over standard input or a list of files. If you just want to read or213write one file see <a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a>.</p>214<p>The typical use is:</p>215<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span><span class="w"> </span><span class="nn">fileinput</span>216<span class="k">for</span> <span class="n">line</span> <span class="ow">in</span> <span class="n">fileinput</span><span class="o">.</span><span class="n">input</span><span class="p">(</span><span class="n">encoding</span><span class="o">=</span><span class="s2">"utf-8"</span><span class="p">):</span>217 <span class="n">process</span><span class="p">(</span><span class="n">line</span><span class="p">)</span>218</pre></div>219</div>220<p>This iterates over the lines of all files listed in <code class="docutils literal notranslate"><span class="pre">sys.argv[1:]</span></code>, defaulting221to <code class="docutils literal notranslate"><span class="pre">sys.stdin</span></code> if the list is empty. If a filename is <code class="docutils literal notranslate"><span class="pre">'-'</span></code>, it is also222replaced by <code class="docutils literal notranslate"><span class="pre">sys.stdin</span></code> and the optional arguments <em>mode</em> and <em>openhook</em>223are ignored. To specify an alternative list of filenames, pass it as the224first argument to <a class="reference internal" href="#fileinput.input" title="fileinput.input"><code class="xref py py-func docutils literal notranslate"><span class="pre">input()</span></code></a>. A single file name is also allowed.</p>225<p>All files are opened in text mode by default, but you can override this by226specifying the <em>mode</em> parameter in the call to <a class="reference internal" href="#fileinput.input" title="fileinput.input"><code class="xref py py-func docutils literal notranslate"><span class="pre">input()</span></code></a> or227<a class="reference internal" href="#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code></a>. If an I/O error occurs during opening or reading a file,228<a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a> is raised.</p>229<div class="versionchanged">230<p><span class="versionmodified changed">Changed in version 3.3: </span><a class="reference internal" href="exceptions.html#IOError" title="IOError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">IOError</span></code></a> used to be raised; it is now an alias of <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a>.</p>231</div>232<p>If <code class="docutils literal notranslate"><span class="pre">sys.stdin</span></code> is used more than once, the second and further use will return233no lines, except perhaps for interactive use, or if it has been explicitly reset234(e.g. using <code class="docutils literal notranslate"><span class="pre">sys.stdin.seek(0)</span></code>).</p>235<p>Empty files are opened and immediately closed; the only time their presence in236the list of filenames is noticeable at all is when the last file opened is237empty.</p>238<p>Lines are returned with any newlines intact, which means that the last line in239a file may not have one.</p>240<p>You can control how files are opened by providing an opening hook via the241<em>openhook</em> parameter to <a class="reference internal" href="#fileinput.input" title="fileinput.input"><code class="xref py py-func docutils literal notranslate"><span class="pre">fileinput.input()</span></code></a> or <a class="reference internal" href="#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-func docutils literal notranslate"><span class="pre">FileInput()</span></code></a>. The242hook must be a function that takes two arguments, <em>filename</em> and <em>mode</em>, and243returns an accordingly opened file-like object. If <em>encoding</em> and/or <em>errors</em>244are specified, they will be passed to the hook as additional keyword arguments.245This module provides a <a class="reference internal" href="#fileinput.hook_compressed" title="fileinput.hook_compressed"><code class="xref py py-func docutils literal notranslate"><span class="pre">hook_compressed()</span></code></a> to support compressed files.</p>246<p>The following function is the primary interface of this module:</p>247<dl class="py function">248<dt class="sig sig-object py" id="fileinput.input">249<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">input</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">files</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">inplace</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">False</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">backup</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">''</span></span></em>, <em class="sig-param"><span class="keyword-only-separator o"><abbr title="Keyword-only parameters separator (PEP 3102)"><span class="pre">*</span></abbr></span></em>, <em class="sig-param"><span class="n"><span class="pre">mode</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">'r'</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">openhook</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">encoding</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">errors</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.input" title="Link to this definition">¶</a></dt>250<dd><p>Create an instance of the <a class="reference internal" href="#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code></a> class. The instance will be used251as global state for the functions of this module, and is also returned to use252during iteration. The parameters to this function will be passed along to the253constructor of the <code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code> class.</p>254<p>The <a class="reference internal" href="#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code></a> instance can be used as a context manager in the255<a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement. In this example, <em>input</em> is closed after the256<code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code> statement is exited, even if an exception occurs:</p>257<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="n">fileinput</span><span class="o">.</span><span class="n">input</span><span class="p">(</span><span class="n">files</span><span class="o">=</span><span class="p">(</span><span class="s1">'spam.txt'</span><span class="p">,</span> <span class="s1">'eggs.txt'</span><span class="p">),</span> <span class="n">encoding</span><span class="o">=</span><span class="s2">"utf-8"</span><span class="p">)</span> <span class="k">as</span> <span class="n">f</span><span class="p">:</span>258 <span class="k">for</span> <span class="n">line</span> <span class="ow">in</span> <span class="n">f</span><span class="p">:</span>259 <span class="n">process</span><span class="p">(</span><span class="n">line</span><span class="p">)</span>260</pre></div>261</div>262<div class="versionchanged">263<p><span class="versionmodified changed">Changed in version 3.2: </span>Can be used as a context manager.</p>264</div>265<div class="versionchanged">266<p><span class="versionmodified changed">Changed in version 3.8: </span>The keyword parameters <em>mode</em> and <em>openhook</em> are now keyword-only.</p>267</div>268<div class="versionchanged">269<p><span class="versionmodified changed">Changed in version 3.10: </span>The keyword-only parameter <em>encoding</em> and <em>errors</em> are added.</p>270</div>271</dd></dl>272 273<p>The following functions use the global state created by <a class="reference internal" href="#fileinput.input" title="fileinput.input"><code class="xref py py-func docutils literal notranslate"><span class="pre">fileinput.input()</span></code></a>;274if there is no active state, <a class="reference internal" href="exceptions.html#RuntimeError" title="RuntimeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">RuntimeError</span></code></a> is raised.</p>275<dl class="py function">276<dt class="sig sig-object py" id="fileinput.filename">277<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">filename</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.filename" title="Link to this definition">¶</a></dt>278<dd><p>Return the name of the file currently being read. Before the first line has279been read, returns <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>280</dd></dl>281 282<dl class="py function">283<dt class="sig sig-object py" id="fileinput.fileno">284<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">fileno</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.fileno" title="Link to this definition">¶</a></dt>285<dd><p>Return the integer “file descriptor” for the current file. When no file is286opened (before the first line and between files), returns <code class="docutils literal notranslate"><span class="pre">-1</span></code>.</p>287</dd></dl>288 289<dl class="py function">290<dt class="sig sig-object py" id="fileinput.lineno">291<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">lineno</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.lineno" title="Link to this definition">¶</a></dt>292<dd><p>Return the cumulative line number of the line that has just been read. Before293the first line has been read, returns <code class="docutils literal notranslate"><span class="pre">0</span></code>. After the last line of the last294file has been read, returns the line number of that line.</p>295</dd></dl>296 297<dl class="py function">298<dt class="sig sig-object py" id="fileinput.filelineno">299<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">filelineno</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.filelineno" title="Link to this definition">¶</a></dt>300<dd><p>Return the line number in the current file. Before the first line has been301read, returns <code class="docutils literal notranslate"><span class="pre">0</span></code>. After the last line of the last file has been read,302returns the line number of that line within the file.</p>303</dd></dl>304 305<dl class="py function">306<dt class="sig sig-object py" id="fileinput.isfirstline">307<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">isfirstline</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.isfirstline" title="Link to this definition">¶</a></dt>308<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the line just read is the first line of its file, otherwise309return <code class="docutils literal notranslate"><span class="pre">False</span></code>.</p>310</dd></dl>311 312<dl class="py function">313<dt class="sig sig-object py" id="fileinput.isstdin">314<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">isstdin</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.isstdin" title="Link to this definition">¶</a></dt>315<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the last line was read from <code class="docutils literal notranslate"><span class="pre">sys.stdin</span></code>, otherwise return316<code class="docutils literal notranslate"><span class="pre">False</span></code>.</p>317</dd></dl>318 319<dl class="py function">320<dt class="sig sig-object py" id="fileinput.nextfile">321<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">nextfile</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.nextfile" title="Link to this definition">¶</a></dt>322<dd><p>Close the current file so that the next iteration will read the first line from323the next file (if any); lines not read from the file will not count towards the324cumulative line count. The filename is not changed until after the first line325of the next file has been read. Before the first line has been read, this326function has no effect; it cannot be used to skip the first file. After the327last line of the last file has been read, this function has no effect.</p>328</dd></dl>329 330<dl class="py function">331<dt class="sig sig-object py" id="fileinput.close">332<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">close</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.close" title="Link to this definition">¶</a></dt>333<dd><p>Close the sequence.</p>334</dd></dl>335 336<p>The class which implements the sequence behavior provided by the module is337available for subclassing as well:</p>338<dl class="py class">339<dt class="sig sig-object py" id="fileinput.FileInput">340<em class="property"><span class="k"><span class="pre">class</span></span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">FileInput</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">files</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">inplace</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">False</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">backup</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">''</span></span></em>, <em class="sig-param"><span class="keyword-only-separator o"><abbr title="Keyword-only parameters separator (PEP 3102)"><span class="pre">*</span></abbr></span></em>, <em class="sig-param"><span class="n"><span class="pre">mode</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">'r'</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">openhook</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">encoding</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">errors</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.FileInput" title="Link to this definition">¶</a></dt>341<dd><p>Class <code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code> is the implementation; its methods <a class="reference internal" href="#fileinput.filename" title="fileinput.filename"><code class="xref py py-meth docutils literal notranslate"><span class="pre">filename()</span></code></a>,342<a class="reference internal" href="#fileinput.fileno" title="fileinput.fileno"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fileno()</span></code></a>, <a class="reference internal" href="#fileinput.lineno" title="fileinput.lineno"><code class="xref py py-meth docutils literal notranslate"><span class="pre">lineno()</span></code></a>, <a class="reference internal" href="#fileinput.filelineno" title="fileinput.filelineno"><code class="xref py py-meth docutils literal notranslate"><span class="pre">filelineno()</span></code></a>, <a class="reference internal" href="#fileinput.isfirstline" title="fileinput.isfirstline"><code class="xref py py-meth docutils literal notranslate"><span class="pre">isfirstline()</span></code></a>,343<a class="reference internal" href="#fileinput.isstdin" title="fileinput.isstdin"><code class="xref py py-meth docutils literal notranslate"><span class="pre">isstdin()</span></code></a>, <a class="reference internal" href="#fileinput.nextfile" title="fileinput.nextfile"><code class="xref py py-meth docutils literal notranslate"><span class="pre">nextfile()</span></code></a> and <a class="reference internal" href="#fileinput.close" title="fileinput.close"><code class="xref py py-meth docutils literal notranslate"><span class="pre">close()</span></code></a> correspond to the344functions of the same name in the module. In addition it is <a class="reference internal" href="../glossary.html#term-iterable"><span class="xref std std-term">iterable</span></a>345and has a <a class="reference internal" href="io.html#io.TextIOBase.readline" title="io.TextIOBase.readline"><code class="xref py py-meth docutils literal notranslate"><span class="pre">readline()</span></code></a> method which returns the next346input line. The sequence must be accessed in strictly sequential order;347random access and <code class="xref py py-meth docutils literal notranslate"><span class="pre">readline()</span></code> cannot be mixed.</p>348<p>With <em>mode</em> you can specify which file mode will be passed to <a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a>. It349must be one of <code class="docutils literal notranslate"><span class="pre">'r'</span></code> and <code class="docutils literal notranslate"><span class="pre">'rb'</span></code>.</p>350<p>The <em>openhook</em>, when given, must be a function that takes two arguments,351<em>filename</em> and <em>mode</em>, and returns an accordingly opened file-like object. You352cannot use <em>inplace</em> and <em>openhook</em> together.</p>353<p>You can specify <em>encoding</em> and <em>errors</em> that is passed to <a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a> or <em>openhook</em>.</p>354<p>A <code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code> instance can be used as a context manager in the355<a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement. In this example, <em>input</em> is closed after the356<code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code> statement is exited, even if an exception occurs:</p>357<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="n">FileInput</span><span class="p">(</span><span class="n">files</span><span class="o">=</span><span class="p">(</span><span class="s1">'spam.txt'</span><span class="p">,</span> <span class="s1">'eggs.txt'</span><span class="p">))</span> <span class="k">as</span> <span class="nb">input</span><span class="p">:</span>358 <span class="n">process</span><span class="p">(</span><span class="nb">input</span><span class="p">)</span>359</pre></div>360</div>361<div class="versionchanged">362<p><span class="versionmodified changed">Changed in version 3.2: </span>Can be used as a context manager.</p>363</div>364<div class="versionchanged">365<p><span class="versionmodified changed">Changed in version 3.8: </span>The keyword parameter <em>mode</em> and <em>openhook</em> are now keyword-only.</p>366</div>367<div class="versionchanged">368<p><span class="versionmodified changed">Changed in version 3.10: </span>The keyword-only parameter <em>encoding</em> and <em>errors</em> are added.</p>369</div>370<div class="versionchanged">371<p><span class="versionmodified changed">Changed in version 3.11: </span>The <code class="docutils literal notranslate"><span class="pre">'rU'</span></code> and <code class="docutils literal notranslate"><span class="pre">'U'</span></code> modes and the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__getitem__()</span></code> method have372been removed.</p>373</div>374</dd></dl>375 376<p><strong>Optional in-place filtering:</strong> if the keyword argument <code class="docutils literal notranslate"><span class="pre">inplace=True</span></code> is377passed to <a class="reference internal" href="#fileinput.input" title="fileinput.input"><code class="xref py py-func docutils literal notranslate"><span class="pre">fileinput.input()</span></code></a> or to the <a class="reference internal" href="#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code></a> constructor, the378file is moved to a backup file and standard output is directed to the input file379(if a file of the same name as the backup file already exists, it will be380replaced silently). This makes it possible to write a filter that rewrites its381input file in place. If the <em>backup</em> parameter is given (typically as382<code class="docutils literal notranslate"><span class="pre">backup='.<some</span> <span class="pre">extension>'</span></code>), it specifies the extension for the backup file,383and the backup file remains around; by default, the extension is <code class="docutils literal notranslate"><span class="pre">'.bak'</span></code> and384it is deleted when the output file is closed. In-place filtering is disabled385when standard input is read.</p>386<p>The two following opening hooks are provided by this module:</p>387<dl class="py function">388<dt class="sig sig-object py" id="fileinput.hook_compressed">389<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">hook_compressed</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">filename</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">mode</span></span></em>, <em class="sig-param"><span class="keyword-only-separator o"><abbr title="Keyword-only parameters separator (PEP 3102)"><span class="pre">*</span></abbr></span></em>, <em class="sig-param"><span class="n"><span class="pre">encoding</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">errors</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.hook_compressed" title="Link to this definition">¶</a></dt>390<dd><p>Transparently opens files compressed with gzip and bzip2 (recognized by the391extensions <code class="docutils literal notranslate"><span class="pre">'.gz'</span></code> and <code class="docutils literal notranslate"><span class="pre">'.bz2'</span></code>) using the <a class="reference internal" href="gzip.html#module-gzip" title="gzip: Interfaces for gzip compression and decompression using file objects."><code class="xref py py-mod docutils literal notranslate"><span class="pre">gzip</span></code></a> and <a class="reference internal" href="bz2.html#module-bz2" title="bz2: Interfaces for bzip2 compression and decompression."><code class="xref py py-mod docutils literal notranslate"><span class="pre">bz2</span></code></a>392modules. If the filename extension is not <code class="docutils literal notranslate"><span class="pre">'.gz'</span></code> or <code class="docutils literal notranslate"><span class="pre">'.bz2'</span></code>, the file is393opened normally (ie, using <a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a> without any decompression).</p>394<p>The <em>encoding</em> and <em>errors</em> values are passed to <a class="reference internal" href="io.html#io.TextIOWrapper" title="io.TextIOWrapper"><code class="xref py py-class docutils literal notranslate"><span class="pre">io.TextIOWrapper</span></code></a>395for compressed files and open for normal files.</p>396<p>Usage example: <code class="docutils literal notranslate"><span class="pre">fi</span> <span class="pre">=</span> <span class="pre">fileinput.FileInput(openhook=fileinput.hook_compressed,</span> <span class="pre">encoding="utf-8")</span></code></p>397<div class="versionchanged">398<p><span class="versionmodified changed">Changed in version 3.10: </span>The keyword-only parameter <em>encoding</em> and <em>errors</em> are added.</p>399</div>400</dd></dl>401 402<dl class="py function">403<dt class="sig sig-object py" id="fileinput.hook_encoded">404<span class="sig-prename descclassname"><span class="pre">fileinput.</span></span><span class="sig-name descname"><span class="pre">hook_encoded</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">encoding</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">errors</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#fileinput.hook_encoded" title="Link to this definition">¶</a></dt>405<dd><p>Returns a hook which opens each file with <a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a>, using the given406<em>encoding</em> and <em>errors</em> to read the file.</p>407<p>Usage example: <code class="docutils literal notranslate"><span class="pre">fi</span> <span class="pre">=</span>408<span class="pre">fileinput.FileInput(openhook=fileinput.hook_encoded("utf-8",</span>409<span class="pre">"surrogateescape"))</span></code></p>410<div class="versionchanged">411<p><span class="versionmodified changed">Changed in version 3.6: </span>Added the optional <em>errors</em> parameter.</p>412</div>413<div class="deprecated">414<p><span class="versionmodified deprecated">Deprecated since version 3.10: </span>This function is deprecated since <a class="reference internal" href="#fileinput.input" title="fileinput.input"><code class="xref py py-func docutils literal notranslate"><span class="pre">fileinput.input()</span></code></a> and <a class="reference internal" href="#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">FileInput</span></code></a>415now have <em>encoding</em> and <em>errors</em> parameters.</p>416</div>417</dd></dl>418 419</section>420 421 422 <div class="clearer"></div>423 </div>424 </div>425 </div>426 <div class="sphinxsidebar" role="navigation" aria-label="Main">427 <div class="sphinxsidebarwrapper">428 <div>429 <h4>Previous topic</h4>430 <p class="topless"><a href="getpass.html"431 title="previous chapter"><code class="xref py py-mod docutils literal notranslate"><span class="pre">getpass</span></code> — Portable password input</a></p>432 </div>433 <div>434 <h4>Next topic</h4>435 <p class="topless"><a href="curses.html"436 title="next chapter"><code class="xref py py-mod docutils literal notranslate"><span class="pre">curses</span></code> — Terminal handling for 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