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| author | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
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| committer | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
| commit | abdaadbcae30fe0c9a66c7516798279fdfd97750 (patch) | |
| tree | 00a54a6e25601e43876d03c1a4a12a749d4a914c /share/doc/cpp/Header-Files.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
Change-Id: I7303388733328cd98ab9aa3c30236db67f2e9e9c
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| -rw-r--r-- | share/doc/cpp/Header-Files.html | 144 |
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diff --git a/share/doc/cpp/Header-Files.html b/share/doc/cpp/Header-Files.html new file mode 100644 index 0000000..4f8c479 --- /dev/null +++ b/share/doc/cpp/Header-Files.html @@ -0,0 +1,144 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1987-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation. A copy of +the license is included in the +section entitled "GNU Free Documentation License". + +This manual contains no Invariant Sections. The Front-Cover Texts are +(a) (see below), and the Back-Cover Texts are (b) (see below). + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>The C Preprocessor: Header Files</title> + +<meta name="description" content="The C Preprocessor: Header Files"> +<meta name="keywords" content="The C Preprocessor: Header Files"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Index-of-Directives.html#Index-of-Directives" rel="index" title="Index of Directives"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="index.html#Top" rel="up" title="Top"> +<link href="Include-Syntax.html#Include-Syntax" rel="next" title="Include Syntax"> +<link href="The-preprocessing-language.html#The-preprocessing-language" rel="previous" title="The preprocessing language"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Header-Files"></a> +<div class="header"> +<p> +Next: <a href="Macros.html#Macros" accesskey="n" rel="next">Macros</a>, Previous: <a href="Overview.html#Overview" accesskey="p" rel="previous">Overview</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</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> +</div> +<hr> +<a name="Header-Files-1"></a> +<h2 class="chapter">2 Header Files</h2> + +<a name="index-header-file"></a> +<p>A header file is a file containing C declarations and macro definitions +(see <a href="Macros.html#Macros">Macros</a>) to be shared between several source files. You request +the use of a header file in your program by <em>including</em> it, with the +C preprocessing directive ‘<samp>#include</samp>’. +</p> +<p>Header files serve two purposes. +</p> +<ul> +<li> <a name="index-system-header-files"></a> +System header files declare the interfaces to parts of the operating +system. You include them in your program to supply the definitions and +declarations you need to invoke system calls and libraries. + +</li><li> Your own header files contain declarations for interfaces between the +source files of your program. Each time you have a group of related +declarations and macro definitions all or most of which are needed in +several different source files, it is a good idea to create a header +file for them. +</li></ul> + +<p>Including a header file produces the same results as copying the header +file into each source file that needs it. Such copying would be +time-consuming and error-prone. With a header file, the related +declarations appear in only one place. If they need to be changed, they +can be changed in one place, and programs that include the header file +will automatically use the new version when next recompiled. The header +file eliminates the labor of finding and changing all the copies as well +as the risk that a failure to find one copy will result in +inconsistencies within a program. +</p> +<p>In C, the usual convention is to give header files names that end with +<samp>.h</samp>. It is most portable to use only letters, digits, dashes, and +underscores in header file names, and at most one dot. +</p> +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="Include-Syntax.html#Include-Syntax" accesskey="1">Include Syntax</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Include-Operation.html#Include-Operation" accesskey="2">Include Operation</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Search-Path.html#Search-Path" accesskey="3">Search Path</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Once_002dOnly-Headers.html#Once_002dOnly-Headers" accesskey="4">Once-Only Headers</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Alternatives-to-Wrapper-_0023ifndef.html#Alternatives-to-Wrapper-_0023ifndef" accesskey="5">Alternatives to Wrapper #ifndef</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Computed-Includes.html#Computed-Includes" accesskey="6">Computed Includes</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Wrapper-Headers.html#Wrapper-Headers" accesskey="7">Wrapper Headers</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="System-Headers.html#System-Headers" accesskey="8">System Headers</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +</table> + +<hr> +<div class="header"> +<p> +Next: <a href="Macros.html#Macros" accesskey="n" rel="next">Macros</a>, Previous: <a href="Overview.html#Overview" accesskey="p" rel="previous">Overview</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</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> +</div> + + + +</body> +</html> |