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diff --git a/share/doc/gdb/Searching-Memory.html b/share/doc/gdb/Searching-Memory.html new file mode 100644 index 0000000..784c1bd --- /dev/null +++ b/share/doc/gdb/Searching-Memory.html @@ -0,0 +1,191 @@ +<!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: Searching Memory</title> + +<meta name="description" content="Debugging with GDB: Searching Memory"> +<meta name="keywords" content="Debugging with GDB: Searching Memory"> +<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="Data.html#Data" rel="up" title="Data"> +<link href="Value-Sizes.html#Value-Sizes" rel="next" title="Value Sizes"> +<link href="Caching-Target-Data.html#Caching-Target-Data" rel="previous" title="Caching Target Data"> +<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="Searching-Memory"></a> +<div class="header"> +<p> +Next: <a href="Value-Sizes.html#Value-Sizes" accesskey="n" rel="next">Value Sizes</a>, Previous: <a href="Caching-Target-Data.html#Caching-Target-Data" accesskey="p" rel="previous">Caching Target Data</a>, Up: <a href="Data.html#Data" accesskey="u" rel="up">Data</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="Search-Memory"></a> +<h3 class="section">10.23 Search Memory</h3> +<a name="index-searching-memory"></a> + +<p>Memory can be searched for a particular sequence of bytes with the +<code>find</code> command. +</p> +<dl compact="compact"> +<dd><a name="index-find"></a> +</dd> +<dt><code>find <span class="roman">[</span>/<var>sn</var><span class="roman">]</span> <var>start_addr</var>, +<var>len</var>, <var>val1</var> <span class="roman">[</span>, <var>val2</var>, …<span class="roman">]</span></code></dt> +<dt><code>find <span class="roman">[</span>/<var>sn</var><span class="roman">]</span> <var>start_addr</var>, <var>end_addr</var>, <var>val1</var> <span class="roman">[</span>, <var>val2</var>, …<span class="roman">]</span></code></dt> +<dd><p>Search memory for the sequence of bytes specified by <var>val1</var>, <var>val2</var>, +etc. The search begins at address <var>start_addr</var> and continues for either +<var>len</var> bytes or through to <var>end_addr</var> inclusive. +</p></dd> +</dl> + +<p><var>s</var> and <var>n</var> are optional parameters. +They may be specified in either order, apart or together. +</p> +<dl compact="compact"> +<dt><span class="roman"><var>s</var>, search query size</span></dt> +<dd><p>The size of each search query value. +</p> +<dl compact="compact"> +<dt><code>b</code></dt> +<dd><p>bytes +</p></dd> +<dt><code>h</code></dt> +<dd><p>halfwords (two bytes) +</p></dd> +<dt><code>w</code></dt> +<dd><p>words (four bytes) +</p></dd> +<dt><code>g</code></dt> +<dd><p>giant words (eight bytes) +</p></dd> +</dl> + +<p>All values are interpreted in the current language. +This means, for example, that if the current source language is C/C<tt>++</tt> +then searching for the string “hello” includes the trailing ’\0’. +The null terminator can be removed from searching by using casts, +e.g.: ‘<samp>{char[5]}"hello"</samp>’. +</p> +<p>If the value size is not specified, it is taken from the +value’s type in the current language. +This is useful when one wants to specify the search +pattern as a mixture of types. +Note that this means, for example, that in the case of C-like languages +a search for an untyped 0x42 will search for ‘<samp>(int) 0x42</samp>’ +which is typically four bytes. +</p> +</dd> +<dt><span class="roman"><var>n</var>, maximum number of finds</span></dt> +<dd><p>The maximum number of matches to print. The default is to print all finds. +</p></dd> +</dl> + +<p>You can use strings as search values. Quote them with double-quotes + (<code>"</code>). +The string value is copied into the search pattern byte by byte, +regardless of the endianness of the target and the size specification. +</p> +<p>The address of each match found is printed as well as a count of the +number of matches found. +</p> +<p>The address of the last value found is stored in convenience variable +‘<samp>$_</samp>’. +A count of the number of matches is stored in ‘<samp>$numfound</samp>’. +</p> +<p>For example, if stopped at the <code>printf</code> in this function: +</p> +<div class="smallexample"> +<pre class="smallexample">void +hello () +{ + static char hello[] = "hello-hello"; + static struct { char c; short s; int i; } + __attribute__ ((packed)) mixed + = { 'c', 0x1234, 0x87654321 }; + printf ("%s\n", hello); +} +</pre></div> + +<p>you get during debugging: +</p> +<div class="smallexample"> +<pre class="smallexample">(gdb) find &hello[0], +sizeof(hello), "hello" +0x804956d <hello.1620+6> +1 pattern found +(gdb) find &hello[0], +sizeof(hello), 'h', 'e', 'l', 'l', 'o' +0x8049567 <hello.1620> +0x804956d <hello.1620+6> +2 patterns found. +(gdb) find &hello[0], +sizeof(hello), {char[5]}"hello" +0x8049567 <hello.1620> +0x804956d <hello.1620+6> +2 patterns found. +(gdb) find /b1 &hello[0], +sizeof(hello), 'h', 0x65, 'l' +0x8049567 <hello.1620> +1 pattern found +(gdb) find &mixed, +sizeof(mixed), (char) 'c', (short) 0x1234, (int) 0x87654321 +0x8049560 <mixed.1625> +1 pattern found +(gdb) print $numfound +$1 = 1 +(gdb) print $_ +$2 = (void *) 0x8049560 +</pre></div> + +<hr> +<div class="header"> +<p> +Next: <a href="Value-Sizes.html#Value-Sizes" accesskey="n" rel="next">Value Sizes</a>, Previous: <a href="Caching-Target-Data.html#Caching-Target-Data" accesskey="p" rel="previous">Caching Target Data</a>, Up: <a href="Data.html#Data" accesskey="u" rel="up">Data</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> |