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102 lines
4.4 KiB
HTML
102 lines
4.4 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html>
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<!-- Copyright (C) 1987-2018 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3 or
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any later version published by the Free Software Foundation. A copy of
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the license is included in the
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section entitled "GNU Free Documentation License".
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This manual contains no Invariant Sections. The Front-Cover Texts are
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(a) (see below), and the Back-Cover Texts are (b) (see below).
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(a) The FSF's Front-Cover Text is:
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A GNU Manual
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(b) The FSF's Back-Cover Text is:
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You have freedom to copy and modify this GNU Manual, like GNU
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software. Copies published by the Free Software Foundation raise
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funds for GNU development. -->
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<!-- Created by GNU Texinfo 6.4, http://www.gnu.org/software/texinfo/ -->
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<head>
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<title>Conditional Syntax (The C Preprocessor)</title>
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<meta name="description" content="Conditional Syntax (The C Preprocessor)">
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<meta name="keywords" content="Conditional Syntax (The C Preprocessor)">
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<link href="index.html#Top" rel="start" title="Top">
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<link href="Index-of-Directives.html#Index-of-Directives" rel="index" title="Index of Directives">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="Conditionals.html#Conditionals" rel="up" title="Conditionals">
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<link href="Ifdef.html#Ifdef" rel="next" title="Ifdef">
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<link href="Conditional-Uses.html#Conditional-Uses" rel="prev" title="Conditional Uses">
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a.summary-letter {text-decoration: none}
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</head>
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<body lang="en">
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<a name="Conditional-Syntax"></a>
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<div class="header">
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<p>
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Next: <a href="Deleted-Code.html#Deleted-Code" accesskey="n" rel="next">Deleted Code</a>, Previous: <a href="Conditional-Uses.html#Conditional-Uses" accesskey="p" rel="prev">Conditional Uses</a>, Up: <a href="Conditionals.html#Conditionals" accesskey="u" rel="up">Conditionals</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index-of-Directives.html#Index-of-Directives" title="Index" rel="index">Index</a>]</p>
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</div>
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<hr>
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<a name="Conditional-Syntax-1"></a>
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<h3 class="section">4.2 Conditional Syntax</h3>
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<a name="index-_0023if"></a>
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<p>A conditional in the C preprocessor begins with a <em>conditional
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directive</em>: ‘<samp>#if</samp>’, ‘<samp>#ifdef</samp>’ or ‘<samp>#ifndef</samp>’.
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</p>
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<table class="menu" border="0" cellspacing="0">
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<tr><td align="left" valign="top">• <a href="Ifdef.html#Ifdef" accesskey="1">Ifdef</a>:</td><td> </td><td align="left" valign="top">
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<tr><td align="left" valign="top">• <a href="If.html#If" accesskey="2">If</a>:</td><td> </td><td align="left" valign="top">
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<tr><td align="left" valign="top">• <a href="Else.html#Else" accesskey="4">Else</a>:</td><td> </td><td align="left" valign="top">
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<tr><td align="left" valign="top">• <a href="Elif.html#Elif" accesskey="5">Elif</a>:</td><td> </td><td align="left" valign="top">
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</html>
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