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<html><head><title>Operators (UNIX in a Nutshell: System V Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Arnold Robbins" /><meta name="DC.Format" content="text/xml" scheme="MIME" /><meta name="DC.Language" content="en-US" /><meta name="DC.Publisher" content="O'Reilly & Associates, Inc." /><meta name="DC.Source" scheme="ISBN" content="1-56592-427-4" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="UNIX in a Nutshell: System V Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img src="gifs/smbanner.gif" usemap="#banner-map" border="0" alt="Book Home" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Book Title" /><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch11_04.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228" /><td align="right" valign="top" width="228"><a href="ch11_06.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr></table></div><h2 class="sect1">11.5. Operators</h2><p><a name="IXT-11-123276" /><a name="IXT-11-123277" />The following table lists the operators,in order of increasing precedence, that are available in <tt class="literal">awk</tt>.Note: while <tt class="literal">**</tt> and <tt class="literal">**=</tt> are common extensions,they are not part of POSIX <tt class="literal">awk</tt>.</p><table border="1" cellpadding="3"><tr><th><em class="emphasis">Symbol</em></th><th><em class="emphasis">Meaning</em></th></tr><tr><td><p><tt class="literal">= += -= *= /= %= ^= **=</tt></p></td><td>Assignment</td></tr><tr><td><tt class="literal">?:</tt></td><td>C conditional expression (<tt class="literal">nawk</tt> only)<a name="IXT-11-123278" /><a name="IXT-11-123279" /><a name="IXT-11-123280" /><a name="IXT-11-123281" /><a name="IXT-11-123282" /><a name="IXT-11-123283" /><a name="IXT-11-123284" /><a name="IXT-11-123285" /></td></tr><tr><td><tt class="literal">||</tt></td><td>Logical OR (short-circuit)<a name="IXT-11-123286" /></td></tr><tr><td><tt class="literal">&&</tt></td><td>Logical AND (short-circuit)<a name="IXT-11-123287" /></td></tr><tr><td><tt class="literal">in</tt></td><td>Array membership (<tt class="literal">nawk</tt> only)</td></tr><tr><td><tt class="literal">~ !~</tt></td><td>Match regular expression and negation<a name="IXT-11-123288" /><a name="IXT-11-123289" /></td></tr><tr><td><tt class="literal">< <= > >= != ==</tt></td><td>Relational operators<a name="IXT-11-123290" /><a name="IXT-11-123291" /><a name="IXT-11-123292" /><a name="IXT-11-123293" /><a name="IXT-11-123294" /><a name="IXT-11-123295" /></td></tr><tr><td>(blank)</td><td>Concatenation</td></tr><tr><td><tt class="literal">+ -</tt></td><td>Addition, subtraction<a name="IXT-11-123296" /><a name="IXT-11-123297" /></td></tr><tr><td><tt class="literal">* / %</tt></td><td>Multiplication, division, and modulus (remainder)<a name="IXT-11-123298" /><a name="IXT-11-123299" /><a name="IXT-11-123300" /></td></tr><tr><td><tt class="literal">+ - !</tt></td><td>Unary plus and minus, and logical negation</td></tr><tr><td><tt class="literal">^ **</tt></td><td>Exponentiation<a name="IXT-11-123301" /><a name="IXT-11-123302" /></td></tr><tr><td><tt class="literal">++ -- </tt></td><td>Increment and decrement, either prefix or postfix<a name="IXT-11-123303" /><a name="IXT-11-123304" /></td></tr><tr><td><tt class="literal">$</tt></td><td>Field reference<a name="IXT-11-123305" /></td></tr></table><p><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch11_04.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img src="../gifs/txthome.gif" alt="Home" border="0" /></a></td><td align="right" valign="top" width="228"><a href="ch11_06.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr><tr><td align="left" valign="top" width="228">11.4. Built-in Variables</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img src="../gifs/index.gif" alt="Book Index" border="0" /></a></td><td align="right" valign="top" width="228">11.6. Variables and Array Assignments</td></tr></table></div><hr width="684" align="left" /><img src="../gifs/navbar.gif" usemap="#library-map" border="0" alt="Library Navigation Links" /><p><p><font size="-1"><a href="copyrght.htm">Copyright © 2003</a> O'Reilly & Associates. 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