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23 <script language="JavaScript" src="../jscript/codes.js"></script><basefont size="3">
24 <center><font size="2">The Open Group Base Specifications Issue 8<br>
25 IEEE Std 1003.1-2024<br>
26 Copyright © 2001-2024 The IEEE and The Open Group</font></center>
27 <hr size="2" noshade>
28 <a name="top" id="top"></a> <a name="readlink" id="readlink"></a> <a name="tag_20_101" id="tag_20_101"></a><!-- readlink -->
29 <h4 class="mansect"><a name="tag_20_101_01" id="tag_20_101_01"></a>NAME</h4>
30 <blockquote>readlink — display the contents of a symbolic link</blockquote>
31 <h4 class="mansect"><a name="tag_20_101_02" id="tag_20_101_02"></a>SYNOPSIS</h4>
32 <blockquote class="synopsis">
33 <p><code><tt>readlink</tt> <b>[</b><tt>-n</tt><b>]</b> <i>file</i></code></p>
34 </blockquote>
35 <h4 class="mansect"><a name="tag_20_101_03" id="tag_20_101_03"></a>DESCRIPTION</h4>
36 <blockquote>
37 <p>If the <i>file</i> operand names a symbolic link, the <i>readlink</i> utility shall not follow the symbolic link when resolving
38 <i>file</i> and shall write the contents of the symbolic link to standard output. If the <b>-n</b> option is not specified, the
39 output to standard output shall be followed by a <newline> character.</p>
40 <p>If <i>file</i> does not name a symbolic link, <i>readlink</i> shall write a diagnostic message to standard error and exit with
41 non-zero status.</p>
42 </blockquote>
43 <h4 class="mansect"><a name="tag_20_101_04" id="tag_20_101_04"></a>OPTIONS</h4>
44 <blockquote>
45 <p>The <i>readlink</i> utility shall conform to XBD <a href="../basedefs/V1_chap12.html#tag_12_02"><i>12.2 Utility Syntax
46 Guidelines</i></a> .</p>
47 <p>The following option shall be supported:</p>
48 <dl compact>
49 <dd></dd>
50 <dt><b>-n</b></dt>
51 <dd>Do not output a trailing <newline> character.</dd>
52 </dl>
53 </blockquote>
54 <h4 class="mansect"><a name="tag_20_101_05" id="tag_20_101_05"></a>OPERANDS</h4>
55 <blockquote>
56 <p>The following operand shall be supported:</p>
57 <dl compact>
58 <dd></dd>
59 <dt><i>file</i></dt>
60 <dd>A pathname of a symbolic link to be read.</dd>
61 </dl>
62 </blockquote>
63 <h4 class="mansect"><a name="tag_20_101_06" id="tag_20_101_06"></a>STDIN</h4>
64 <blockquote>
65 <p>Not used.</p>
66 </blockquote>
67 <h4 class="mansect"><a name="tag_20_101_07" id="tag_20_101_07"></a>INPUT FILES</h4>
68 <blockquote>
69 <p>None.</p>
70 </blockquote>
71 <h4 class="mansect"><a name="tag_20_101_08" id="tag_20_101_08"></a>ENVIRONMENT VARIABLES</h4>
72 <blockquote>
73 <p>The following environment variables shall affect the execution of <i>readlink</i>:</p>
74 <dl compact>
75 <dd></dd>
76 <dt><i>LANG</i></dt>
77 <dd>Provide a default value for the internationalization variables that are unset or null. (See XBD <a href=
78 "../basedefs/V1_chap08.html#tag_08_02"><i>8.2 Internationalization Variables</i></a> for the precedence of internationalization
79 variables used to determine the values of locale categories.)</dd>
80 <dt><i>LC_ALL</i></dt>
81 <dd>If set to a non-empty string value, override the values of all the other internationalization variables.</dd>
82 <dt><i>LC_CTYPE</i></dt>
83 <dd>Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as
84 opposed to multi-byte characters in arguments and input files).</dd>
85 <dt><i>LC_MESSAGES</i></dt>
86 <dd><br>
87 Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.</dd>
88 <dt><i>NLSPATH</i></dt>
89 <dd><sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
90 Determine the location of messages objects and message catalogs. <img src="../images/opt-end.gif" alt="[Option End]" border=
91 "0"></dd>
92 </dl>
93 </blockquote>
94 <h4 class="mansect"><a name="tag_20_101_09" id="tag_20_101_09"></a>ASYNCHRONOUS EVENTS</h4>
95 <blockquote>
96 <p>Default.</p>
97 </blockquote>
98 <h4 class="mansect"><a name="tag_20_101_10" id="tag_20_101_10"></a>STDOUT</h4>
99 <blockquote>
100 <p>See DESCRIPTION.</p>
101 </blockquote>
102 <h4 class="mansect"><a name="tag_20_101_11" id="tag_20_101_11"></a>STDERR</h4>
103 <blockquote>
104 <p>The standard error shall be used only for diagnostic messages.</p>
105 </blockquote>
106 <h4 class="mansect"><a name="tag_20_101_12" id="tag_20_101_12"></a>OUTPUT FILES</h4>
107 <blockquote>
108 <p>None.</p>
109 </blockquote>
110 <h4 class="mansect"><a name="tag_20_101_13" id="tag_20_101_13"></a>EXTENDED DESCRIPTION</h4>
111 <blockquote>
112 <p>None.</p>
113 </blockquote>
114 <h4 class="mansect"><a name="tag_20_101_14" id="tag_20_101_14"></a>EXIT STATUS</h4>
115 <blockquote>
116 <p>The following exit values shall be returned:</p>
117 <dl compact>
118 <dd></dd>
119 <dt> 0</dt>
120 <dd>Successful completion.</dd>
121 <dt>>0</dt>
122 <dd>An error occurred.</dd>
123 </dl>
124 </blockquote>
125 <h4 class="mansect"><a name="tag_20_101_15" id="tag_20_101_15"></a>CONSEQUENCES OF ERRORS</h4>
126 <blockquote>
127 <p>Default.</p>
128 </blockquote>
129 <hr>
130 <div class="box"><em>The following sections are informative.</em></div>
131 <h4 class="mansect"><a name="tag_20_101_16" id="tag_20_101_16"></a>APPLICATION USAGE</h4>
132 <blockquote>
133 <p>None.</p>
134 </blockquote>
135 <h4 class="mansect"><a name="tag_20_101_17" id="tag_20_101_17"></a>EXAMPLES</h4>
136 <blockquote>
137 <p>None.</p>
138 </blockquote>
139 <h4 class="mansect"><a name="tag_20_101_18" id="tag_20_101_18"></a>RATIONALE</h4>
140 <blockquote>
141 <p>The <i>readlink</i> utility was added because using <a href="../utilities/ls.html"><i>ls</i></a> <b>-l</b> to obtain the
142 contents of a symbolic link is difficult if the output includes more than one occurrence of the string <tt>" -> "</tt>.</p>
143 <p>The <b>-f</b> option found in many implementations was not included, as the <a href=
144 "../utilities/realpath.html"><i>realpath</i></a> utility provides equivalent functionality with a choice of behaviors.</p>
145 </blockquote>
146 <h4 class="mansect"><a name="tag_20_101_19" id="tag_20_101_19"></a>FUTURE DIRECTIONS</h4>
147 <blockquote>
148 <p>None.</p>
149 </blockquote>
150 <h4 class="mansect"><a name="tag_20_101_20" id="tag_20_101_20"></a>SEE ALSO</h4>
151 <blockquote>
152 <p><a href="../utilities/ln.html#"><i>ln</i></a> , <a href="../utilities/ls.html#"><i>ls</i></a> , <a href=
153 "../utilities/realpath.html#tag_20_102"><i>realpath</i></a></p>
154 <p>XBD <a href="../basedefs/V1_chap08.html#tag_08"><i>8. Environment Variables</i></a> , <a href=
155 "../basedefs/V1_chap12.html#tag_12_02"><i>12.2 Utility Syntax Guidelines</i></a></p>
156 <p>XSH <a href="../functions/readlink.html#"><i>readlink</i></a></p>
157 </blockquote>
158 <h4 class="mansect"><a name="tag_20_101_21" id="tag_20_101_21"></a>CHANGE HISTORY</h4>
159 <blockquote>
160 <p>First released in Issue 8.</p>
161 </blockquote>
162 <div class="box"><em>End of informative text.</em></div>
163 <hr>
164 <p> </p>
165 <a href="#top"><span class="topOfPage">return to top of page</span></a><br>
166 <hr size="2" noshade>
167 <center><font size="2">UNIX® is a registered Trademark of The Open Group.<br>
168 POSIX™ is a Trademark of The IEEE.<br>
169 Copyright © 2001-2024 The IEEE and The Open Group, All Rights Reserved<br>
170 [ <a href="../mindex.html">Main Index</a> | <a href="../basedefs/contents.html">XBD</a> | <a href=
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172 ]</font></center>
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