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<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"/><meta name="viewport" content="width=device-width, initial-scale=0.8"/><title>15.1&nbsp;Paths</title><link rel="stylesheet" type="text/css" href="../scribble.css" title="default"/><link rel="stylesheet" type="text/css" href="extras.css" title="default"/><link rel="stylesheet" type="text/css" href="../racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-style.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../doc-site.css" title="default"/><script type="text/javascript" src="../scribble-common.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../doc-site.js"></script><script type="text/javascript" src="../local-redirect/local-redirect.js"></script><script type="text/javascript" src="../local-redirect/local-user-redirect.js"></script><!--[if IE 6]><style type="text/css">.SIEHidden { overflow: hidden; }</style><![endif]--></head><body id="doc-racket-lang-org"><div class="tocset"><div class="tocview"><div class="tocviewlist tocviewlisttopspace"><div class="tocviewtitle"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,&quot;tocview_0&quot;);">&#9658;</a></td><td></td><td><a href="index.html" class="tocviewlink" data-pltdoc="x">The Racket Reference</a></td></tr></table></div><div class="tocviewsublisttop" style="display: none;" id="tocview_0"><table cellspacing="0" cellpadding="0"><tr><td align="right">1&nbsp;</td><td><a href="model.html" class="tocviewlink" data-pltdoc="x">Language Model</a></td></tr><tr><td align="right">2&nbsp;</td><td><a href="notation.html" class="tocviewlink" data-pltdoc="x">Notation for Documentation</a></td></tr><tr><td align="right">3&nbsp;</td><td><a href="syntax.html" class="tocviewlink" data-pltdoc="x">Syntactic Forms</a></td></tr><tr><td align="right">4&nbsp;</td><td><a href="data.html" class="tocviewlink" data-pltdoc="x">Datatypes</a></td></tr><tr><td align="right">5&nbsp;</td><td><a href="structures.html" class="tocviewlink" data-pltdoc="x">Structures</a></td></tr><tr><td align="right">6&nbsp;</td><td><a href="mzlib_class.html" class="tocviewlink" data-pltdoc="x">Classes and Objects</a></td></tr><tr><td align="right">7&nbsp;</td><td><a href="mzlib_unit.html" class="tocviewlink" data-pltdoc="x">Units</a></td></tr><tr><td align="right">8&nbsp;</td><td><a href="contracts.html" class="tocviewlink" data-pltdoc="x">Contracts</a></td></tr><tr><td align="right">9&nbsp;</td><td><a href="match.html" class="tocviewlink" data-pltdoc="x">Pattern Matching</a></td></tr><tr><td align="right">10&nbsp;</td><td><a href="control.html" class="tocviewlink" data-pltdoc="x">Control Flow</a></td></tr><tr><td align="right">11&nbsp;</td><td><a href="concurrency.html" class="tocviewlink" data-pltdoc="x">Concurrency and Parallelism</a></td></tr><tr><td align="right">12&nbsp;</td><td><a href="Macros.html" class="tocviewlink" data-pltdoc="x">Macros</a></td></tr><tr><td align="right">13&nbsp;</td><td><a href="input-and-output.html" class="tocviewlink" data-pltdoc="x">Input and Output</a></td></tr><tr><td align="right">14&nbsp;</td><td><a href="security.html" class="tocviewlink" data-pltdoc="x">Reflection and Security</a></td></tr><tr><td align="right">15&nbsp;</td><td><a href="os.html" class="tocviewselflink" data-pltdoc="x">Operating System</a></td></tr><tr><td align="right">16&nbsp;</td><td><a href="memory.html" class="tocviewlink" data-pltdoc="x">Memory Management</a></td></tr><tr><td align="right">17&nbsp;</td><td><a href="unsafe.html" class="tocviewlink" data-pltdoc="x">Unsafe Operations</a></td></tr><tr><td align="right">18&nbsp;</td><td><a href="running.html" class="tocviewlink
path can be provided either as a string or as an instance of the
<a name="(tech._path)"></a><span style="font-style: italic">path</span> datatype. If a string is provided, it is converted to a
path using <span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._string-~3epath%29%29" class="RktValLink" data-pltdoc="x">string-&gt;path</a></span>. Beware that some paths may not
be representable as strings; see <a href="unixpaths.html#%28part._unixpathrep%29" data-pltdoc="x">Unix Path Representation</a> and
<a href="windowspaths.html#%28part._windowspathrep%29" data-pltdoc="x">Windows Path Representation</a> for more information.
A Racket procedure that generates a
filesystem path always generates a <a href="pathutils.html#%28tech._path%29" class="techoutside" data-pltdoc="x"><span class="techinside">path</span></a> value.</p><p>By default, paths are created and manipulated for the current
platform, but procedures that merely manipulate paths (without using
the filesystem) can manipulate paths using conventions for other
supported platforms. The <span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._bytes-~3epath%29%29" class="RktValLink" data-pltdoc="x">bytes-&gt;path</a></span> procedure accepts an
optional argument that indicates the platform for the path, either
<span class="RktVal">'</span><span class="RktVal">unix</span> or <span class="RktVal">'</span><span class="RktVal">windows</span>. For other functions, such as
<span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._build-path%29%29" class="RktValLink" data-pltdoc="x">build-path</a></span> or <span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._simplify-path%29%29" class="RktValLink" data-pltdoc="x">simplify-path</a></span>, the behavior is
sensitive to the kind of path that is supplied. Unless otherwise
specified, a procedure that requires a path accepts only paths for the
current platform.</p><p>Two <a href="pathutils.html#%28tech._path%29" class="techoutside" data-pltdoc="x"><span class="techinside">path</span></a> values are <span class="RktSym"><a href="Equality.html#%28def._%28%28quote._~23~25kernel%29._equal~3f%29%29" class="RktValLink" data-pltdoc="x">equal?</a></span> when they are use the same
convention type and when their byte-string representations are
<span class="RktSym"><a href="Equality.html#%28def._%28%28quote._~23~25kernel%29._equal~3f%29%29" class="RktValLink" data-pltdoc="x">equal?</a></span>. A path string (or byte string) cannot be empty, and
it cannot contain a nul character or byte. When an empty string or a
string containing nul is provided as a path to any procedure except
<span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._absolute-path~3f%29%29" class="RktValLink" data-pltdoc="x">absolute-path?</a></span>, <span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._relative-path~3f%29%29" class="RktValLink" data-pltdoc="x">relative-path?</a></span>, or
<span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._complete-path~3f%29%29" class="RktValLink" data-pltdoc="x">complete-path?</a></span>, the <span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p>Most Racket primitives that accept paths first <a name="(tech._cleanse)"></a><span style="font-style: italic">cleanse</span> the
path before using it. Procedures that build paths or merely check the
form of a path do not cleanse paths, with the exceptions of
<span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._cleanse-path%29%29" class="RktValLink" data-pltdoc="x">cleanse-path</a></span>, <span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._expand-user-path%29%29" class="RktValLink" data-pltdoc="x">expand-user-path</a></span>, and
<span class="RktSym"><a href="Manipulating_Paths.html#%28def._%28%28quote._~23~25kernel%29._simplify-path%29%29" class="RktValLink" data-pltdoc="x">simplify-path</a></span>. For more information about path cleansing and
other platform-specific details, see <a href="unixpaths.html" data-pltdoc="x">Unix and Mac OS Paths</a> and
<a href="windowspaths.html" data-pltdoc="x">Windows Paths</a>.</p><div class="navsetbottom"><span class="navleft"><form class="searchform"><input class="searchbox" id="searchbox" type="text" tabindex="1" placeholder="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, &quot;8.6&quot;, &quot;../&quot;);"/></form>&nbsp;&nbsp;<a href="https://docs.racket-lang.org/index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot(&quot;8.6&quot;);">top</a><span class="tocsettoggle">&nbsp;&nbsp;<a href="javascript:void(0);" title="show/hide table of contents" onclick="TocsetToggle();">contents</a></span></span><span class="navright">&nbsp;&nbsp;<a href="os.html" title="backward to &quot;15 Operating System&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="os.html" title="up to &quot;15 Operating System&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="Manipulating_Paths.html" title="forward to &quot;15.1.1 Manipulating Paths&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div></div></div><div id="contextindicator">&nbsp;</div></body></html>