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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta name="generator" content="HTML Tidy, see www.w3.org"><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><link type="text/css" rel="stylesheet" href="style.css"><!-- Generated by The Open Group's rhtm tool v1.2.1 --><!-- Copyright (c) 2001-2004 IEEE and The Open Group, All Rights Reserved --><title>pwd</title></head><body bgcolor="white"><script type="text/javascript" language="JavaScript" src="../jscript/codes.js"></script><basefont size="3"> <a name="pwd"></a> <a name="tag_04_105"></a><!-- pwd --> <!--header start--><center><font size="2">The Open Group Base Specifications Issue 6<br>IEEE Std 1003.1, 2004 Edition<br>Copyright © 2001-2004 The IEEE and The Open Group, All Rights reserved.</font></center><!--header end--><hr size="2" noshade><h4><a name="tag_04_105_01"></a>NAME</h4><blockquote>pwd - return working directory name</blockquote><h4><a name="tag_04_105_02"></a>SYNOPSIS</h4><blockquote class="synopsis"><p><code><tt>pwd</tt> <b>[</b><tt>-L | -P</tt> <b>]</b></code></p></blockquote><h4><a name="tag_04_105_03"></a>DESCRIPTION</h4><blockquote><p>The <i>pwd</i> utility shall write to standard output an absolute pathname of the current working directory, which does notcontain the filenames dot or dot-dot.</p></blockquote><h4><a name="tag_04_105_04"></a>OPTIONS</h4><blockquote><p>The <i>pwd</i> utility shall conform to the Base Definitions volume of IEEE Std 1003.1-2001, <a href="../basedefs/xbd_chap12.html#tag_12_02">Section 12.2, Utility Syntax Guidelines</a>.</p><p>The following options shall be supported by the implementation:</p><dl compact><dt><b>-L</b></dt><dd>If the <i>PWD</i> environment variable contains an absolute pathname of the current directory that does not contain thefilenames dot or dot-dot, <i>pwd</i> shall write this pathname to standard output. Otherwise, the <b>-L</b> option shall behave asthe <b>-P</b> option.</dd><dt><b>-P</b></dt><dd>The absolute pathname written shall not contain filenames that, in the context of the pathname, refer to files of type symboliclink.</dd></dl><p>If both <b>-L</b> and <b>-P</b> are specified, the last one shall apply. If neither <b>-L</b> nor <b>-P</b> is specified, the<i>pwd</i> utility shall behave as if <b>-L</b> had been specified.</p></blockquote><h4><a name="tag_04_105_05"></a>OPERANDS</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_06"></a>STDIN</h4><blockquote><p>Not used.</p></blockquote><h4><a name="tag_04_105_07"></a>INPUT FILES</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_08"></a>ENVIRONMENT VARIABLES</h4><blockquote><p>The following environment variables shall affect the execution of <i>pwd</i>:</p><dl compact><dt><i>LANG</i></dt><dd>Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume ofIEEE Std 1003.1-2001, <a href="../basedefs/xbd_chap08.html#tag_08_02">Section 8.2, Internationalization Variables</a> forthe precedence of internationalization variables used to determine the values of locale categories.)</dd><dt><i>LC_ALL</i></dt><dd>If set to a non-empty string value, override the values of all the other internationalization variables.</dd><dt><i>LC_MESSAGES</i></dt><dd>Determine the locale that should be used to affect the format and contents of diagnostic messages written to standarderror.</dd><dt><i>NLSPATH</i></dt><dd><sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">Determine the location of message catalogs for the processing of <i>LC_MESSAGES .</i> <img src="../images/opt-end.gif" alt="[Option End]" border="0"></dd><dt><i>PWD</i></dt><dd>If the <b>-P</b> option is in effect, this variable shall be set to an absolute pathname of the current working directory thatdoes not contain any components that specify symbolic links, does not contain any components that are dot, and does not contain anycomponents that are dot-dot. If an application sets or unsets the value of <i>PWD ,</i> the behavior of <i>pwd</i> isunspecified.</dd></dl></blockquote><h4><a name="tag_04_105_09"></a>ASYNCHRONOUS EVENTS</h4><blockquote><p>Default.</p></blockquote><h4><a name="tag_04_105_10"></a>STDOUT</h4><blockquote><p>The <i>pwd</i> utility output is an absolute pathname of the current working directory:</p><pre><tt>"%s\n", <</tt><i>directory pathname</i><tt>></tt></pre></blockquote><h4><a name="tag_04_105_11"></a>STDERR</h4><blockquote><p>The standard error shall be used only for diagnostic messages.</p></blockquote><h4><a name="tag_04_105_12"></a>OUTPUT FILES</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_13"></a>EXTENDED DESCRIPTION</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_14"></a>EXIT STATUS</h4><blockquote><p>The following exit values shall be returned:</p><dl compact><dt> 0</dt><dd>Successful completion.</dd><dt>>0</dt><dd>An error occurred.</dd></dl></blockquote><h4><a name="tag_04_105_15"></a>CONSEQUENCES OF ERRORS</h4><blockquote><p>If an error is detected, output shall not be written to standard output, a diagnostic message shall be written to standarderror, and the exit status is not zero.</p></blockquote><hr><div class="box"><em>The following sections are informative.</em></div><h4><a name="tag_04_105_16"></a>APPLICATION USAGE</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_17"></a>EXAMPLES</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_18"></a>RATIONALE</h4><blockquote><p>Some implementations have historically provided <i>pwd</i> as a shell special built-in command.</p><p>In most utilities, if an error occurs, partial output may be written to standard output. This does not happen in historicalimplementations of <i>pwd</i>. Because <i>pwd</i> is frequently used in historical shell scripts without checking the exit status,it is important that the historical behavior is required here; therefore, the CONSEQUENCES OF ERRORS section specifically disallowsany partial output being written to standard output.</p></blockquote><h4><a name="tag_04_105_19"></a>FUTURE DIRECTIONS</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_105_20"></a>SEE ALSO</h4><blockquote><p><a href="cd.html"><i>cd</i></a>, the System Interfaces volume of IEEE Std 1003.1-2001, <a href="../functions/getcwd.html"><i>getcwd</i>()</a></p></blockquote><h4><a name="tag_04_105_21"></a>CHANGE HISTORY</h4><blockquote><p>First released in Issue 2.</p></blockquote><h4><a name="tag_04_105_22"></a>Issue 6</h4><blockquote><p>The <b>-P</b> and <b>-L</b> options are added to describe actions relating to symbolic links as specified in theIEEE P1003.2b draft standard.</p></blockquote><div class="box"><em>End of informative text.</em></div><hr size="2" noshade><center><font size="2"><!--footer start-->UNIX ® is a registered Trademark of The Open Group.<br>POSIX ® is a registered Trademark of The IEEE.<br>[ <a href="../mindex.html">Main Index</a> | <a href="../basedefs/contents.html">XBD</a> | <a href="../utilities/contents.html">XCU</a> | <a href="../functions/contents.html">XSH</a> | <a href="../xrat/contents.html">XRAT</a>]</font></center><!--footer end--><hr size="2" noshade></body></html>⌨️ 快捷键说明
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