| <html lang="en"> |
| <head> |
| <title>Invoking GDB - Debugging with GDB</title> |
| <meta http-equiv="Content-Type" content="text/html"> |
| <meta name="description" content="Debugging with GDB"> |
| <meta name="generator" content="makeinfo 4.13"> |
| <link title="Top" rel="start" href="index.html#Top"> |
| <link rel="up" href="Invocation.html#Invocation" title="Invocation"> |
| <link rel="next" href="Quitting-GDB.html#Quitting-GDB" title="Quitting GDB"> |
| <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> |
| <!-- |
| Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
| 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 |
| 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.''--> |
| <meta http-equiv="Content-Style-Type" content="text/css"> |
| <style type="text/css"><!-- |
| pre.display { font-family:inherit } |
| pre.format { font-family:inherit } |
| pre.smalldisplay { font-family:inherit; font-size:smaller } |
| pre.smallformat { font-family:inherit; font-size:smaller } |
| pre.smallexample { font-size:smaller } |
| pre.smalllisp { font-size:smaller } |
| span.sc { font-variant:small-caps } |
| span.roman { font-family:serif; font-weight:normal; } |
| span.sansserif { font-family:sans-serif; font-weight:normal; } |
| --></style> |
| <link rel="stylesheet" type="text/css" href="../cs.css"> |
| </head> |
| <body> |
| <div class="node"> |
| <a name="Invoking-GDB"></a> |
| <p> |
| Next: <a rel="next" accesskey="n" href="Quitting-GDB.html#Quitting-GDB">Quitting GDB</a>, |
| Up: <a rel="up" accesskey="u" href="Invocation.html#Invocation">Invocation</a> |
| <hr> |
| </div> |
| |
| <h3 class="section">2.1 Invoking <span class="sc">gdb</span></h3> |
| |
| <p>Invoke <span class="sc">gdb</span> by running the program <code>gdb</code>. Once started, |
| <span class="sc">gdb</span> reads commands from the terminal until you tell it to exit. |
| |
| <p>You can also run <code>gdb</code> with a variety of arguments and options, |
| to specify more of your debugging environment at the outset. |
| |
| <p>The command-line options described here are designed |
| to cover a variety of situations; in some environments, some of these |
| options may effectively be unavailable. |
| |
| <p>The most usual way to start <span class="sc">gdb</span> is with one argument, |
| specifying an executable program: |
| |
| <pre class="smallexample"> gdb <var>program</var> |
| </pre> |
| <p class="noindent">You can also start with both an executable program and a core file |
| specified: |
| |
| <pre class="smallexample"> gdb <var>program</var> <var>core</var> |
| </pre> |
| <p>You can, instead, specify a process ID as a second argument, if you want |
| to debug a running process: |
| |
| <pre class="smallexample"> gdb <var>program</var> 1234 |
| </pre> |
| <p class="noindent">would attach <span class="sc">gdb</span> to process <code>1234</code> (unless you also have a file |
| named <samp><span class="file">1234</span></samp>; <span class="sc">gdb</span> does check for a core file first). |
| |
| <p>Taking advantage of the second command-line argument requires a fairly |
| complete operating system; when you use <span class="sc">gdb</span> as a remote |
| debugger attached to a bare board, there may not be any notion of |
| “process”, and there is often no way to get a core dump. <span class="sc">gdb</span> |
| will warn you if it is unable to attach or to read core dumps. |
| |
| <p>You can optionally have <code>gdb</code> pass any arguments after the |
| executable file to the inferior using <code>--args</code>. This option stops |
| option processing. |
| <pre class="smallexample"> gdb --args gcc -O2 -c foo.c |
| </pre> |
| <p>This will cause <code>gdb</code> to debug <code>gcc</code>, and to set |
| <code>gcc</code>'s command-line arguments (see <a href="Arguments.html#Arguments">Arguments</a>) to ‘<samp><span class="samp">-O2 -c foo.c</span></samp>’. |
| |
| <p>You can run <code>gdb</code> without printing the front material, which describes |
| <span class="sc">gdb</span>'s non-warranty, by specifying <code>-silent</code>: |
| |
| <pre class="smallexample"> gdb -silent |
| </pre> |
| <p class="noindent">You can further control how <span class="sc">gdb</span> starts up by using command-line |
| options. <span class="sc">gdb</span> itself can remind you of the options available. |
| |
| <p class="noindent">Type |
| |
| <pre class="smallexample"> gdb -help |
| </pre> |
| <p class="noindent">to display all available options and briefly describe their use |
| (‘<samp><span class="samp">gdb -h</span></samp>’ is a shorter equivalent). |
| |
| <p>All options and command line arguments you give are processed |
| in sequential order. The order makes a difference when the |
| ‘<samp><span class="samp">-x</span></samp>’ option is used. |
| |
| <ul class="menu"> |
| <li><a accesskey="1" href="File-Options.html#File-Options">File Options</a>: Choosing files |
| <li><a accesskey="2" href="Mode-Options.html#Mode-Options">Mode Options</a>: Choosing modes |
| <li><a accesskey="3" href="Startup.html#Startup">Startup</a>: What <span class="sc">gdb</span> does during startup |
| </ul> |
| |
| </body></html> |
| |
