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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) 2001-2003 The Open Group, All Rights Reserved --><title>shift</title></head><body bgcolor="white"><basefont size="3"> <a name="shift"></a> <a name="tag_04_129"></a><!-- shift --> <!--header start--><center><font size="2">The Open Group Base Specifications Issue 6<br>IEEE Std 1003.1, 2003 Edition<br>Copyright © 2001-2003 The IEEE and The Open Group, All Rights reserved.</font></center><!--header end--><hr size="2" noshade><h4><a name="tag_04_129_01"></a>NAME</h4><blockquote>shift - shift positional parameters</blockquote><h4><a name="tag_04_129_02"></a>SYNOPSIS</h4><blockquote class="synopsis"><p><code><tt>shift</tt> <b>[</b><i>n</i><b>]</b></code></p></blockquote><h4><a name="tag_04_129_03"></a>DESCRIPTION</h4><blockquote><p>The positional parameters shall be shifted. Positional parameter 1 shall be assigned the value of parameter (1+<i>n</i>),parameter 2 shall be assigned the value of parameter (2+<i>n</i>), and so on. The parameters represented by the numbers<tt>"$#"</tt> down to <tt>"$#-n+1"</tt> shall be unset, and the parameter <tt>'#'</tt> is updated to reflect the new number ofpositional parameters.</p><p>The value <i>n</i> shall be an unsigned decimal integer less than or equal to the value of the special parameter <tt>'#'</tt> .If <i>n</i> is not given, it shall be assumed to be 1. If <i>n</i> is 0, the positional and special parameters are not changed.</p></blockquote><h4><a name="tag_04_129_04"></a>OPTIONS</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_05"></a>OPERANDS</h4><blockquote><p>See the DESCRIPTION.</p></blockquote><h4><a name="tag_04_129_06"></a>STDIN</h4><blockquote><p>Not used.</p></blockquote><h4><a name="tag_04_129_07"></a>INPUT FILES</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_08"></a>ENVIRONMENT VARIABLES</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_09"></a>ASYNCHRONOUS EVENTS</h4><blockquote><p>Default.</p></blockquote><h4><a name="tag_04_129_10"></a>STDOUT</h4><blockquote><p>Not used.</p></blockquote><h4><a name="tag_04_129_11"></a>STDERR</h4><blockquote><p>The standard error shall be used only for diagnostic messages.</p></blockquote><h4><a name="tag_04_129_12"></a>OUTPUT FILES</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_13"></a>EXTENDED DESCRIPTION</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_14"></a>EXIT STATUS</h4><blockquote><p>The exit status is >0 if <i>n</i>>$#; otherwise, it is zero.</p></blockquote><h4><a name="tag_04_129_15"></a>CONSEQUENCES OF ERRORS</h4><blockquote><p>Default.</p></blockquote><hr><div class="box"><em>The following sections are informative.</em></div><h4><a name="tag_04_129_16"></a>APPLICATION USAGE</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_17"></a>EXAMPLES</h4><blockquote><pre><b>$</b> <tt>set a b c d e</tt><b>$</b> <tt>shift 2</tt><b>$</b> <tt>echo $*</tt><b>c d e</b></pre></blockquote><h4><a name="tag_04_129_18"></a>RATIONALE</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_19"></a>FUTURE DIRECTIONS</h4><blockquote><p>None.</p></blockquote><h4><a name="tag_04_129_20"></a>SEE ALSO</h4><blockquote><p><a href="xcu_chap02.html#tag_02_14"><i>Special Built-In Utilities</i></a></p></blockquote><h4><a name="tag_04_129_21"></a>CHANGE HISTORY</h4><h4><a name="tag_04_129_22"></a>Issue 6</h4><blockquote><p>IEEE Std 1003.1-2001/Cor 1-2002, item XCU/TC1/D6/5 is applied so that the reference page sections use terms asdescribed in the Utility Description Defaults ( <a href="xcu_chap01.html#tag_01_11"><i>Utility Description Defaults</i></a> ). Nochange in behavior is intended.</p></blockquote><div class="box"><em>End of informative text.</em></div><hr><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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