1<html lang="en"> 2<head> 3<title>Predefined Macros - The C Preprocessor</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="The C Preprocessor"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="Macros.html#Macros" title="Macros"> 9<link rel="prev" href="Variadic-Macros.html#Variadic-Macros" title="Variadic Macros"> 10<link rel="next" href="Undefining-and-Redefining-Macros.html#Undefining-and-Redefining-Macros" title="Undefining and Redefining Macros"> 11<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 12<!-- 13Copyright (C) 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 141997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 152008, 2009, 2010, 2011 16Free Software Foundation, Inc. 17 18Permission is granted to copy, distribute and/or modify this document 19under the terms of the GNU Free Documentation License, Version 1.3 or 20any later version published by the Free Software Foundation. A copy of 21the license is included in the 22section entitled ``GNU Free Documentation License''. 23 24This manual contains no Invariant Sections. The Front-Cover Texts are 25(a) (see below), and the Back-Cover Texts are (b) (see below). 26 27(a) The FSF's Front-Cover Text is: 28 29 A GNU Manual 30 31(b) The FSF's Back-Cover Text is: 32 33 You have freedom to copy and modify this GNU Manual, like GNU 34 software. Copies published by the Free Software Foundation raise 35 funds for GNU development. 36--> 37<meta http-equiv="Content-Style-Type" content="text/css"> 38<style type="text/css"><!-- 39 pre.display { font-family:inherit } 40 pre.format { font-family:inherit } 41 pre.smalldisplay { font-family:inherit; font-size:smaller } 42 pre.smallformat { font-family:inherit; font-size:smaller } 43 pre.smallexample { font-size:smaller } 44 pre.smalllisp { font-size:smaller } 45 span.sc { font-variant:small-caps } 46 span.roman { font-family:serif; font-weight:normal; } 47 span.sansserif { font-family:sans-serif; font-weight:normal; } 48--></style> 49<link rel="stylesheet" type="text/css" href="../cs.css"> 50</head> 51<body> 52<div class="node"> 53<a name="Predefined-Macros"></a> 54<p> 55Next: <a rel="next" accesskey="n" href="Undefining-and-Redefining-Macros.html#Undefining-and-Redefining-Macros">Undefining and Redefining Macros</a>, 56Previous: <a rel="previous" accesskey="p" href="Variadic-Macros.html#Variadic-Macros">Variadic Macros</a>, 57Up: <a rel="up" accesskey="u" href="Macros.html#Macros">Macros</a> 58<hr> 59</div> 60 61<h3 class="section">3.7 Predefined Macros</h3> 62 63<p><a name="index-predefined-macros-59"></a>Several object-like macros are predefined; you use them without 64supplying their definitions. They fall into three classes: standard, 65common, and system-specific. 66 67 <p>In C++, there is a fourth category, the named operators. They act like 68predefined macros, but you cannot undefine them. 69 70<ul class="menu"> 71<li><a accesskey="1" href="Standard-Predefined-Macros.html#Standard-Predefined-Macros">Standard Predefined Macros</a> 72<li><a accesskey="2" href="Common-Predefined-Macros.html#Common-Predefined-Macros">Common Predefined Macros</a> 73<li><a accesskey="3" href="System_002dspecific-Predefined-Macros.html#System_002dspecific-Predefined-Macros">System-specific Predefined Macros</a> 74<li><a accesskey="4" href="C_002b_002b-Named-Operators.html#C_002b_002b-Named-Operators">C++ Named Operators</a> 75</ul> 76 77 </body></html> 78 79