172 lines
3.9 KiB
HTML
172 lines
3.9 KiB
HTML
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<link type="text/css" rel="stylesheet" href="style.css"><!-- Generated by The Open Group's rhtm tool v1.2.1 -->
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<!-- Copyright (c) 2001 The Open Group, All Rights Reserved -->
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<title>eval</title>
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<body bgcolor="white">
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<basefont size="3"> <a name="eval"></a> <a name="tag_04_44"></a><!-- eval -->
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<!--header start-->
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<center><font size="2">The Open Group Base Specifications Issue 6<br>
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IEEE Std 1003.1-2001<br>
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Copyright © 2001 The IEEE and The Open Group, All Rights reserved.</font></center>
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<!--header end-->
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<hr size="2" noshade>
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<h4><a name="tag_04_44_01"></a>NAME</h4>
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<blockquote>eval - construct command by concatenating arguments</blockquote>
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<h4><a name="tag_04_44_02"></a>SYNOPSIS</h4>
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<blockquote class="synopsis">
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<p><code><tt>eval</tt> <b>[</b><i>argument</i> <tt>...</tt><b>]</b></code></p>
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</blockquote>
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<h4><a name="tag_04_44_03"></a>DESCRIPTION</h4>
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<blockquote>
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<p>The <i>eval</i> utility shall construct a command by concatenating <i>argument</i>s together, separating each with a
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<space>. The constructed command shall be read and executed by the shell.</p>
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</blockquote>
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<h4><a name="tag_04_44_04"></a>OPTIONS</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_05"></a>OPERANDS</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_06"></a>STDIN</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_07"></a>INPUT FILES</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_08"></a>ENVIRONMENT VARIABLES</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_09"></a>ASYNCHRONOUS EVENTS</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_10"></a>STDOUT</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_11"></a>STDERR</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_12"></a>OUTPUT FILES</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_13"></a>EXTENDED DESCRIPTION</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_14"></a>EXIT STATUS</h4>
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<blockquote>
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<p>If there are no <i>argument</i>s, or only null arguments, <i>eval</i> shall return a zero exit status; otherwise, it shall
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return the exit status of the command defined by the string of concatenated <i>argument</i>s separated by <space>s.</p>
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</blockquote>
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<h4><a name="tag_04_44_15"></a>CONSEQUENCES OF ERRORS</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<hr>
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<div class="box"><em>The following sections are informative.</em></div>
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<h4><a name="tag_04_44_16"></a>APPLICATION USAGE</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_17"></a>EXAMPLES</h4>
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<blockquote>
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<pre>
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<tt>foo=10 x=foo
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y='$'$x
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echo $y
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</tt><b>$foo</b><tt>eval y='$'$x
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echo $y
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</tt><b>10</b>
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</pre>
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</blockquote>
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<h4><a name="tag_04_44_18"></a>RATIONALE</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_19"></a>FUTURE DIRECTIONS</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<h4><a name="tag_04_44_20"></a>SEE ALSO</h4>
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<blockquote>
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<p><a href="xcu_chap02.html#tag_02_14"><i>Special Built-In Utilities</i></a></p>
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</blockquote>
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<h4><a name="tag_04_44_21"></a>CHANGE HISTORY</h4>
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<blockquote>
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<p>None.</p>
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</blockquote>
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<div class="box"><em>End of informative text.</em></div>
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UNIX ® is a registered Trademark of The Open Group.<br>
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POSIX ® is a registered Trademark of The IEEE.<br>
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