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diff --git a/share/doc/gdb/Break-Commands.html b/share/doc/gdb/Break-Commands.html new file mode 100644 index 0000000..472e325 --- /dev/null +++ b/share/doc/gdb/Break-Commands.html @@ -0,0 +1,175 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 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; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: Break Commands</title> + +<meta name="description" content="Debugging with GDB: Break Commands"> +<meta name="keywords" content="Debugging with GDB: Break Commands"> +<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="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Breakpoints.html#Breakpoints" rel="up" title="Breakpoints"> +<link href="Dynamic-Printf.html#Dynamic-Printf" rel="next" title="Dynamic Printf"> +<link href="Conditions.html#Conditions" rel="previous" title="Conditions"> +<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="Break-Commands"></a> +<div class="header"> +<p> +Next: <a href="Dynamic-Printf.html#Dynamic-Printf" accesskey="n" rel="next">Dynamic Printf</a>, Previous: <a href="Conditions.html#Conditions" accesskey="p" rel="previous">Conditions</a>, Up: <a href="Breakpoints.html#Breakpoints" accesskey="u" rel="up">Breakpoints</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> +</div> +<hr> +<a name="Breakpoint-Command-Lists"></a> +<h4 class="subsection">5.1.7 Breakpoint Command Lists</h4> + +<a name="index-breakpoint-commands"></a> +<p>You can give any breakpoint (or watchpoint or catchpoint) a series of +commands to execute when your program stops due to that breakpoint. For +example, you might want to print the values of certain expressions, or +enable other breakpoints. +</p> +<dl compact="compact"> +<dd><a name="index-commands"></a> +<a name="index-end-_0028breakpoint-commands_0029"></a> +</dd> +<dt><code>commands <span class="roman">[</span><var>list</var>…<span class="roman">]</span></code></dt> +<dt><code>… <var>command-list</var> …</code></dt> +<dt><code>end</code></dt> +<dd><p>Specify a list of commands for the given breakpoints. The commands +themselves appear on the following lines. Type a line containing just +<code>end</code> to terminate the commands. +</p> +<p>To remove all commands from a breakpoint, type <code>commands</code> and +follow it immediately with <code>end</code>; that is, give no commands. +</p> +<p>With no argument, <code>commands</code> refers to the last breakpoint, +watchpoint, or catchpoint set (not to the breakpoint most recently +encountered). If the most recent breakpoints were set with a single +command, then the <code>commands</code> will apply to all the breakpoints +set by that command. This applies to breakpoints set by +<code>rbreak</code>, and also applies when a single <code>break</code> command +creates multiple breakpoints (see <a href="Ambiguous-Expressions.html#Ambiguous-Expressions">Ambiguous +Expressions</a>). +</p></dd> +</dl> + +<p>Pressing <tt class="key">RET</tt> as a means of repeating the last <small>GDB</small> command is +disabled within a <var>command-list</var>. +</p> +<p>Inside a command list, you can use the command +<kbd>disable $_hit_bpnum</kbd> to disable the encountered breakpoint. +</p> +<p>If your breakpoint has several code locations, the command +<kbd>disable $_hit_bpnum.$_hit_locno</kbd> will disable the specific breakpoint +code location encountered. If the breakpoint has only one location, +this command will disable the encountered breakpoint. +</p> +<p>You can use breakpoint commands to start your program up again. Simply +use the <code>continue</code> command, or <code>step</code>, or any other command +that resumes execution. +</p> +<p>Any other commands in the command list, after a command that resumes +execution, are ignored. This is because any time you resume execution +(even with a simple <code>next</code> or <code>step</code>), you may encounter +another breakpoint—which could have its own command list, leading to +ambiguities about which list to execute. +</p> +<a name="index-silent"></a> +<p>If the first command you specify in a command list is <code>silent</code>, the +usual message about stopping at a breakpoint is not printed. This may +be desirable for breakpoints that are to print a specific message and +then continue. If none of the remaining commands print anything, you +see no sign that the breakpoint was reached. <code>silent</code> is +meaningful only at the beginning of a breakpoint command list. +</p> +<p>The commands <code>echo</code>, <code>output</code>, and <code>printf</code> allow you to +print precisely controlled output, and are often useful in silent +breakpoints. See <a href="Output.html#Output">Commands for Controlled Output</a>. +</p> +<p>For example, here is how you could use breakpoint commands to print the +value of <code>x</code> at entry to <code>foo</code> whenever <code>x</code> is positive. +</p> +<div class="smallexample"> +<pre class="smallexample">break foo if x>0 +commands +silent +printf "x is %d\n",x +cont +end +</pre></div> + +<p>One application for breakpoint commands is to compensate for one bug so +you can test for another. Put a breakpoint just after the erroneous line +of code, give it a condition to detect the case in which something +erroneous has been done, and give it commands to assign correct values +to any variables that need them. End with the <code>continue</code> command +so that your program does not stop, and start with the <code>silent</code> +command so that no output is produced. Here is an example: +</p> +<div class="smallexample"> +<pre class="smallexample">break 403 +commands +silent +set x = y + 4 +cont +end +</pre></div> + +<hr> +<div class="header"> +<p> +Next: <a href="Dynamic-Printf.html#Dynamic-Printf" accesskey="n" rel="next">Dynamic Printf</a>, Previous: <a href="Conditions.html#Conditions" accesskey="p" rel="previous">Conditions</a>, Up: <a href="Breakpoints.html#Breakpoints" accesskey="u" rel="up">Breakpoints</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> +</div> + + + +</body> +</html> |