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<!-- -->
<!-- -->
<p><strong>with-open-file</strong> <span><i>macro</i></span></p>
<p><strong>Syntax:</strong></p>
<p><span><b>with-open-file</b></span> (<em>stream filespec {options}</em>*) <span><i>{declaration}</i></span>* <span><i>{form}</i></span>*</p>
<p>→ results</p>
<p><strong>Arguments and Values:</strong></p>
<p><span><i>stream</i></span> – a variable.</p>
<p><em>filespec</em>—a <span><i>pathname designator</i></span> .</p>
<p><em>options</em> – <span><i>forms</i></span>; evaluated.</p>
<p><span><i>declaration</i></span>—a <span><b>declare</b></span> <span><i>expression</i></span>; not evaluated.</p>
<p><span><i>forms</i></span>—an <span><i>implicit progn</i></span>.</p>
<p><em>results</em>—the <span><i>values</i></span> returned by the <span><i>forms</i></span>.</p>
<p><strong>Description:</strong></p>
<p><span><b>with-open-file</b></span> uses <span><b>open</b></span> to create a <span><i>file stream</i></span> to <span><i>file</i></span> named by <em>filespec</em>. <em>Filespec</em> is the name of the file to be opened. <em>Options</em> are used as keyword arguments to <span><b>open</b></span>.</p>
<p>The <em>stream object</em> to which the <span><i>stream variable</i></span> is <span><i>bound</i></span> has <span><i>dynamic extent</i></span>; its <span><i>extent</i></span> ends when the <span><i>form</i></span> is exited.</p>
<p><span><b>with-open-file</b></span> evaluates the <span><i>forms</i></span> as an <span><i>implicit progn</i></span> with <span><i>stream</i></span> bound to the value returned by <span><b>open</b></span>.</p>
<p>When control leaves the body, either normally or abnormally (such as by use of <span><b>throw</b></span>), the file is automatically closed. If a new output file is being written, and control leaves abnormally, the file is aborted and the file system is left, so far as possible, as if the file had never been opened.</p>
<span><b>with-open-file</b></span>
<p>It is possible by the use of <!-- -->:if-exists<!-- --> nil or <!-- -->:if-does-not-exist<!-- --> nil for <span><i>stream</i></span> to be bound to <span><b>nil</b></span>. Users of <!-- -->:if-does-not-exist<!-- --> nil should check for a valid <span><i>stream</i></span>.</p>
<p>The consequences are undefined if an attempt is made to <span><i>assign</i></span> the <span><i>stream variable</i></span>. The compiler may choose to issue a warning if such an attempt is detected.</p>
<p><strong>Examples:</strong></p>
<div class="language-lisp codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-lisp codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style="color:#00009f">setq</span><span class="token plain"> p </span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">merge-pathnames</span><span class="token plain"> </span><span class="token string" style="color:#e3116c">&quot;test&quot;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">→ #&lt;PATHNAME </span><span class="token lisp-property property" style="color:#36acaa">:HOST</span><span class="token plain"> NIL </span><span class="token lisp-property property" style="color:#36acaa">:DEVICE</span><span class="token plain"> *device-name* </span><span class="token lisp-property property" style="color:#36acaa">:DIRECTORY</span><span class="token plain"> *directory-name* </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token lisp-property property" style="color:#36acaa">:NAME</span><span class="token plain"> </span><span class="token string" style="color:#e3116c">&quot;test&quot;</span><span class="token plain"> </span><span class="token lisp-property property" style="color:#36acaa">:TYPE</span><span class="token plain"> NIL </span><span class="token lisp-property property" style="color:#36acaa">:VERSION</span><span class="token plain"> </span><span class="token lisp-property property" style="color:#36acaa">:NEWEST&gt;</span><span class="token plain"> </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">with-open-file</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">s</span><span class="token plain"> p </span><span class="token lisp-property property" style="color:#36acaa">:direction</span><span class="token plain"> </span><span class="token lisp-property property" style="color:#36acaa">:output</span><span class="token plain"> </span><span class="token lisp-property property" style="color:#36acaa">:if-exists</span><span class="token plain"> </span><span class="token lisp-property property" style="color:#36acaa">:supersede</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">format</span><span class="token plain"> s </span><span class="token string" style="color:#e3116c">&quot;Here are a couple~%of test data lines~%&quot;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> → NIL </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">with-open-file</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">s</span><span class="token plain"> p</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style="color:#00009f">do<
<p><strong>Side Effects:</strong></p>
<p>Creates a <span><i>stream</i></span> to the <span><i>file</i></span> named by <span><i>filename</i></span> (upon entry), and closes the <span><i>stream</i></span> (upon exit). In some <span><i>implementations</i></span>, the <span><i>file</i></span> might be locked in some way while it is open. If the <span><i>stream</i></span> is an <em>output stream</em>, a <span><i>file</i></span> might be created.</p>
<p><strong>Affected By:</strong></p>
<p>The host computer’s file system.</p>
<p><strong>Exceptional Situations:</strong></p>
<p>See the <span><i>function</i></span> <span><b>open</b></span>.</p>
<p><strong>See Also:</strong></p>
<p><span><b>open</b></span>, <span><b>close</b></span>, <span><b>pathname</b></span>, <span><b>logical-pathname</b></span>, Section 19.1.2 (Pathnames as Filenames)</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="expanded-reference-with-open-file">Expanded Reference: with-open-file<a href="with-open-file_macro.html#expanded-reference-with-open-file" class="hash-link" aria-label="Direct link to Expanded Reference: with-open-file" title="Direct link to Expanded Reference: with-open-file">​</a></h2>
<div class="theme-admonition theme-admonition-tip admonition_xJq3 alert alert--success"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 12 16"><path fill-rule="evenodd" d="M6.5 0C3.48 0 1 2.19 1 5c0 .92.55 2.25 1 3 1.34 2.25 1.78 2.78 2 4v1h5v-1c.22-1.22.66-1.75 2-4 .45-.75 1-2.08 1-3 0-2.81-2.48-5-5.5-5zm3.64 7.48c-.25.44-.47.8-.67 1.11-.86 1.41-1.25 2.06-1.45 3.23-.02.05-.02.11-.02.17H5c0-.06 0-.13-.02-.17-.2-1.17-.59-1.83-1.45-3.23-.2-.31-.42-.67-.67-1.11C2.44 6.78 2 5.65 2 5c0-2.2 2.02-4 4.5-4 1.22 0 2.36.42 3.22 1.19C10.55 2.94 11 3.94 11 5c0 .66-.44 1.78-.86 2.48zM4 14h5c-.23 1.14-1.3 2-2.5 2s-2.27-.86-2.5-2z"></path></svg></span>tip</div><div class="admonitionContent_BuS1"><p>TODO: Please contribute to this page by adding explanations and examples</p></div></div>
<div class="language-lisp codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-lisp codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token punctuation" style="color:#393A34">(</span><span class="token car">with-open-file</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">)</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><footer class="theme-doc-footer docusaurus-mt-lg"><div class="theme-doc-footer-edit-meta-row row"><div class="col"><a href="https://github.com/lisp-docs/cl-language-reference/tree/main/docs/chap-21/cb-c-dictionary/with-open-file_macro.md" target="_blank" rel="noopener noreferrer" class="theme-edit-this-page"><svg fill="currentColor" height="20" width="20" viewBox="0 0 40 40" class="iconEdit_Z9Sw" aria-hidden="true"><g><path d="m34.5 11.7l-3 3.1-6.3-6.3 3.1-3q0.5-0.5 1.2-0.5t1.1 0.5l3.9 3.9q0.5 0.4 0.5 1.1t-0.5 1.2z m-29.5 17.1l18.4-18.5 6.3 6.3-18.4 18.4h-6.3v-6.2z"></path></g></svg>Edit this page</a></div><div class="col lastUpdated_vwxv"><span class="theme-last-updated">Last updated<!-- --> by <b>daninus14</b></span></div></div></footer></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="with-input-from-string_macro.html"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">with-input-from-string</div></a><a class="pagination-nav__link pagination-nav__link--next" href="with-open-stream_macro.html"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">with-open-stream</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="with-open-file_macro.html#expanded-reference-with-open-file" class="table-of-contents__link toc-highlight">Expanded Reference: with-open-file</a></li></ul></div></div></div></div></main></div></div></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Docs</div><ul class="footer__items clean-list"><li class="footer__item"><a href="../../../docs/tutorial.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Common Lisp Tutorial</a></li><li class="footer__item"><a href="../../index.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Common Lisp Technical Reference</a></li><li class="footer__item"><a href="../../../docs/help.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Help</a></li></ul></div><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://stackoverflow.com/questions/tagged/common-lisp" target="_blank" rel="noopener noreferrer" class="footer__link-item">Stack Overflow<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="htt
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