1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Copyright (C) 1988-2021 Free Software Foundation, Inc. 4 5Permission is granted to copy, distribute and/or modify this document 6under the terms of the GNU Free Documentation License, Version 1.3 or 7any later version published by the Free Software Foundation; with the 8Invariant Sections being "Free Software" and "Free Software Needs 9Free Documentation", with the Front-Cover Texts being "A GNU Manual," 10and with the Back-Cover Texts as in (a) below. 11 12(a) The FSF's Back-Cover Text is: "You are free to copy and modify 13this GNU Manual. Buying copies from GNU Press supports the FSF in 14developing GNU and promoting software freedom." --> 15<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> 16<head> 17<title>Debugging with GDB: Edit</title> 18 19<meta name="description" content="Debugging with GDB: Edit"> 20<meta name="keywords" content="Debugging with GDB: Edit"> 21<meta name="resource-type" content="document"> 22<meta name="distribution" content="global"> 23<meta name="Generator" content="makeinfo"> 24<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 25<link href="index.html#Top" rel="start" title="Top"> 26<link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> 27<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> 28<link href="Source.html#Source" rel="up" title="Source"> 29<link href="Search.html#Search" rel="next" title="Search"> 30<link href="Address-Locations.html#Address-Locations" rel="previous" title="Address Locations"> 31<style type="text/css"> 32<!-- 33a.summary-letter {text-decoration: none} 34blockquote.smallquotation {font-size: smaller} 35div.display {margin-left: 3.2em} 36div.example {margin-left: 3.2em} 37div.indentedblock {margin-left: 3.2em} 38div.lisp {margin-left: 3.2em} 39div.smalldisplay {margin-left: 3.2em} 40div.smallexample {margin-left: 3.2em} 41div.smallindentedblock {margin-left: 3.2em; font-size: smaller} 42div.smalllisp {margin-left: 3.2em} 43kbd {font-style:oblique} 44pre.display {font-family: inherit} 45pre.format {font-family: inherit} 46pre.menu-comment {font-family: serif} 47pre.menu-preformatted {font-family: serif} 48pre.smalldisplay {font-family: inherit; font-size: smaller} 49pre.smallexample {font-size: smaller} 50pre.smallformat {font-family: inherit; font-size: smaller} 51pre.smalllisp {font-size: smaller} 52span.nocodebreak {white-space:nowrap} 53span.nolinebreak {white-space:nowrap} 54span.roman {font-family:serif; font-weight:normal} 55span.sansserif {font-family:sans-serif; font-weight:normal} 56ul.no-bullet {list-style: none} 57--> 58</style> 59 60 61</head> 62 63<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> 64<a name="Edit"></a> 65<div class="header"> 66<p> 67Next: <a href="Search.html#Search" accesskey="n" rel="next">Search</a>, Previous: <a href="Specify-Location.html#Specify-Location" accesskey="p" rel="previous">Specify Location</a>, Up: <a href="Source.html#Source" accesskey="u" rel="up">Source</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> 68</div> 69<hr> 70<a name="Editing-Source-Files"></a> 71<h3 class="section">9.3 Editing Source Files</h3> 72<a name="index-editing-source-files"></a> 73 74<a name="index-edit"></a> 75<a name="index-e-_0028edit_0029"></a> 76<p>To edit the lines in a source file, use the <code>edit</code> command. 77The editing program of your choice 78is invoked with the current line set to 79the active line in the program. 80Alternatively, there are several ways to specify what part of the file you 81want to print if you want to see other parts of the program: 82</p> 83<dl compact="compact"> 84<dt><code>edit <var>location</var></code></dt> 85<dd><p>Edit the source file specified by <code>location</code>. Editing starts at 86that <var>location</var>, e.g., at the specified source line of the 87specified file. See <a href="Specify-Location.html#Specify-Location">Specify Location</a>, for all the possible forms 88of the <var>location</var> argument; here are the forms of the <code>edit</code> 89command most commonly used: 90</p> 91<dl compact="compact"> 92<dt><code>edit <var>number</var></code></dt> 93<dd><p>Edit the current source file with <var>number</var> as the active line number. 94</p> 95</dd> 96<dt><code>edit <var>function</var></code></dt> 97<dd><p>Edit the file containing <var>function</var> at the beginning of its definition. 98</p></dd> 99</dl> 100 101</dd> 102</dl> 103 104<a name="Choosing-Your-Editor"></a> 105<h4 class="subsection">9.3.1 Choosing Your Editor</h4> 106<p>You can customize <small>GDB</small> to use any editor you want 107<a name="DOCF10" href="#FOOT10"><sup>10</sup></a>. 108By default, it is <samp>/bin/ex</samp>, but you can change this 109by setting the environment variable <code>EDITOR</code> before using 110<small>GDB</small>. For example, to configure <small>GDB</small> to use the 111<code>vi</code> editor, you could use these commands with the <code>sh</code> shell: 112</p><div class="smallexample"> 113<pre class="smallexample">EDITOR=/usr/bin/vi 114export EDITOR 115gdb … 116</pre></div> 117<p>or in the <code>csh</code> shell, 118</p><div class="smallexample"> 119<pre class="smallexample">setenv EDITOR /usr/bin/vi 120gdb … 121</pre></div> 122 123<div class="footnote"> 124<hr> 125<h4 class="footnotes-heading">Footnotes</h4> 126 127<h3><a name="FOOT10" href="#DOCF10">(10)</a></h3> 128<p>The only restriction is that your editor (say <code>ex</code>), recognizes the 129following command-line syntax: 130</p><div class="smallexample"> 131<pre class="smallexample">ex +<var>number</var> file 132</pre></div> 133<p>The optional numeric value +<var>number</var> specifies the number of the line in 134the file where to start editing.</p> 135</div> 136 137 138 139</body> 140</html> 141