| <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> |
| <html> |
| <!-- Copyright (C) 1988-2015 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 5.2, 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="prev" 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="prev">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> |
| <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="prev">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> |
