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diff --git a/share/doc/gdb/Attach.html b/share/doc/gdb/Attach.html new file mode 100644 index 0000000..4de6928 --- /dev/null +++ b/share/doc/gdb/Attach.html @@ -0,0 +1,166 @@ +<!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: Attach</title> + +<meta name="description" content="Debugging with GDB: Attach"> +<meta name="keywords" content="Debugging with GDB: Attach"> +<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="Running.html#Running" rel="up" title="Running"> +<link href="Kill-Process.html#Kill-Process" rel="next" title="Kill Process"> +<link href="Input_002fOutput.html#Input_002fOutput" rel="previous" title="Input/Output"> +<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="Attach"></a> +<div class="header"> +<p> +Next: <a href="Kill-Process.html#Kill-Process" accesskey="n" rel="next">Kill Process</a>, Previous: <a href="Input_002fOutput.html#Input_002fOutput" accesskey="p" rel="previous">Input/Output</a>, Up: <a href="Running.html#Running" accesskey="u" rel="up">Running</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="Debugging-an-Already_002drunning-Process"></a> +<h3 class="section">4.7 Debugging an Already-running Process</h3> +<a name="index-attach-1"></a> +<a name="index-attach"></a> + +<dl compact="compact"> +<dt><code>attach <var>process-id</var></code></dt> +<dd><p>This command attaches to a running process—one that was started +outside <small>GDB</small>. (<code>info files</code> shows your active +targets.) The command takes as argument a process ID. The usual way to +find out the <var>process-id</var> of a Unix process is with the <code>ps</code> utility, +or with the ‘<samp>jobs -l</samp>’ shell command. +</p> +<p><code>attach</code> does not repeat if you press <tt class="key">RET</tt> a second time after +executing the command. +</p></dd> +</dl> + +<p>To use <code>attach</code>, your program must be running in an environment +which supports processes; for example, <code>attach</code> does not work for +programs on bare-board targets that lack an operating system. You must +also have permission to send the process a signal. +</p> +<p>When you use <code>attach</code>, the debugger finds the program running in +the process first by looking in the current working directory, then (if +the program is not found) by using the source file search path +(see <a href="Source-Path.html#Source-Path">Specifying Source Directories</a>). You can also use +the <code>file</code> command to load the program. See <a href="Files.html#Files">Commands to +Specify Files</a>. +</p> +<a name="set-exec_002dfile_002dmismatch"></a><p>If the debugger can determine that the executable file running in the +process it is attaching to does not match the current exec-file loaded +by <small>GDB</small>, the option <code>exec-file-mismatch</code> specifies how to +handle the mismatch. <small>GDB</small> tries to compare the files by +comparing their build IDs (see <a href="Separate-Debug-Files.html#build-ID">build ID</a>), if available. +</p> +<dl compact="compact"> +<dd><a name="index-exec_002dfile_002dmismatch"></a> +<a name="index-set-exec_002dfile_002dmismatch"></a> +</dd> +<dt><code>set exec-file-mismatch ‘<samp>ask|warn|off</samp>’</code></dt> +<dd> +<p>Whether to detect mismatch between the current executable file loaded +by <small>GDB</small> and the executable file used to start the process. If +‘<samp>ask</samp>’, the default, display a warning and ask the user whether to +load the process executable file; if ‘<samp>warn</samp>’, just display a +warning; if ‘<samp>off</samp>’, don’t attempt to detect a mismatch. +If the user confirms loading the process executable file, then its symbols +will be loaded as well. +</p> +<a name="index-show-exec_002dfile_002dmismatch"></a> +</dd> +<dt><code>show exec-file-mismatch</code></dt> +<dd><p>Show the current value of <code>exec-file-mismatch</code>. +</p> +</dd> +</dl> + +<p>The first thing <small>GDB</small> does after arranging to debug the specified +process is to stop it. You can examine and modify an attached process +with all the <small>GDB</small> commands that are ordinarily available when +you start processes with <code>run</code>. You can insert breakpoints; you +can step and continue; you can modify storage. If you would rather the +process continue running, you may use the <code>continue</code> command after +attaching <small>GDB</small> to the process. +</p> +<dl compact="compact"> +<dd><a name="index-detach"></a> +</dd> +<dt><code>detach</code></dt> +<dd><p>When you have finished debugging the attached process, you can use the +<code>detach</code> command to release it from <small>GDB</small> control. Detaching +the process continues its execution. After the <code>detach</code> command, +that process and <small>GDB</small> become completely independent once more, and you +are ready to <code>attach</code> another process or start one with <code>run</code>. +<code>detach</code> does not repeat if you press <tt class="key">RET</tt> again after +executing the command. +</p></dd> +</dl> + +<p>If you exit <small>GDB</small> while you have an attached process, you detach +that process. If you use the <code>run</code> command, you kill that process. +By default, <small>GDB</small> asks for confirmation if you try to do either of these +things; you can control whether or not you need to confirm by using the +<code>set confirm</code> command (see <a href="Messages_002fWarnings.html#Messages_002fWarnings">Optional Warnings and +Messages</a>). +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Kill-Process.html#Kill-Process" accesskey="n" rel="next">Kill Process</a>, Previous: <a href="Input_002fOutput.html#Input_002fOutput" accesskey="p" rel="previous">Input/Output</a>, Up: <a href="Running.html#Running" accesskey="u" rel="up">Running</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> |