1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Copyright (C) 1988-2021 Free Software Foundation, Inc. 4 5Permission is granted to copy, distribute and/or modify this document 6under the terms of the GNU Free Documentation License, Version 1.3 or 7any later version published by the Free Software Foundation; with the 8Invariant Sections being "Free Software" and "Free Software Needs 9Free Documentation", with the Front-Cover Texts being "A GNU Manual," 10and with the Back-Cover Texts as in (a) below. 11 12(a) The FSF's Back-Cover Text is: "You are free to copy and modify 13this GNU Manual. 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This is 75the same as if the arguments were specified by the ‘<samp>-se</samp>’ and 76‘<samp>-c</samp>’ (or ‘<samp>-p</samp>’) options respectively. (<small>GDB</small> reads the 77first argument that does not have an associated option flag as 78equivalent to the ‘<samp>-se</samp>’ option followed by that argument; and the 79second argument that does not have an associated option flag, if any, as 80equivalent to the ‘<samp>-c</samp>’/‘<samp>-p</samp>’ option followed by that argument.) 81If the second argument begins with a decimal digit, <small>GDB</small> will 82first attempt to attach to it as a process, and if that fails, attempt 83to open it as a corefile. If you have a corefile whose name begins with 84a digit, you can prevent <small>GDB</small> from treating it as a pid by 85prefixing it with <samp>./</samp>, e.g. <samp>./12345</samp>. 86</p> 87<p>If <small>GDB</small> has not been configured to included core file support, 88such as for most embedded targets, then it will complain about a second 89argument and ignore it. 90</p> 91<p>Many options have both long and short forms; both are shown in the 92following list. <small>GDB</small> also recognizes the long forms if you truncate 93them, so long as enough of the option is present to be unambiguous. 94(If you prefer, you can flag option arguments with ‘<samp>--</samp>’ rather 95than ‘<samp>-</samp>’, though we illustrate the more usual convention.) 96</p> 97 98<dl compact="compact"> 99<dt><code>-symbols <var>file</var></code></dt> 100<dt><code>-s <var>file</var></code></dt> 101<dd><a name="index-_002d_002dsymbols"></a> 102<a name="index-_002ds"></a> 103<p>Read symbol table from file <var>file</var>. 104</p> 105</dd> 106<dt><code>-exec <var>file</var></code></dt> 107<dt><code>-e <var>file</var></code></dt> 108<dd><a name="index-_002d_002dexec"></a> 109<a name="index-_002de"></a> 110<p>Use file <var>file</var> as the executable file to execute when appropriate, 111and for examining pure data in conjunction with a core dump. 112</p> 113</dd> 114<dt><code>-se <var>file</var></code></dt> 115<dd><a name="index-_002d_002dse"></a> 116<p>Read symbol table from file <var>file</var> and use it as the executable 117file. 118</p> 119</dd> 120<dt><code>-core <var>file</var></code></dt> 121<dt><code>-c <var>file</var></code></dt> 122<dd><a name="index-_002d_002dcore"></a> 123<a name="index-_002dc"></a> 124<p>Use file <var>file</var> as a core dump to examine. 125</p> 126</dd> 127<dt><code>-pid <var>number</var></code></dt> 128<dt><code>-p <var>number</var></code></dt> 129<dd><a name="index-_002d_002dpid"></a> 130<a name="index-_002dp"></a> 131<p>Connect to process ID <var>number</var>, as with the <code>attach</code> command. 132</p> 133</dd> 134<dt><code>-command <var>file</var></code></dt> 135<dt><code>-x <var>file</var></code></dt> 136<dd><a name="index-_002d_002dcommand"></a> 137<a name="index-_002dx"></a> 138<p>Execute commands from file <var>file</var>. The contents of this file is 139evaluated exactly as the <code>source</code> command would. 140See <a href="Command-Files.html#Command-Files">Command files</a>. 141</p> 142</dd> 143<dt><code>-eval-command <var>command</var></code></dt> 144<dt><code>-ex <var>command</var></code></dt> 145<dd><a name="index-_002d_002deval_002dcommand"></a> 146<a name="index-_002dex"></a> 147<p>Execute a single <small>GDB</small> command. 148</p> 149<p>This option may be used multiple times to call multiple commands. It may 150also be interleaved with ‘<samp>-command</samp>’ as required. 151</p> 152<div class="smallexample"> 153<pre class="smallexample">gdb -ex 'target sim' -ex 'load' \ 154 -x setbreakpoints -ex 'run' a.out 155</pre></div> 156 157</dd> 158<dt><code>-init-command <var>file</var></code></dt> 159<dt><code>-ix <var>file</var></code></dt> 160<dd><a name="index-_002d_002dinit_002dcommand"></a> 161<a name="index-_002dix"></a> 162<p>Execute commands from file <var>file</var> before loading the inferior (but 163after loading gdbinit files). 164See <a href="Startup.html#Startup">Startup</a>. 165</p> 166</dd> 167<dt><code>-init-eval-command <var>command</var></code></dt> 168<dt><code>-iex <var>command</var></code></dt> 169<dd><a name="index-_002d_002dinit_002deval_002dcommand"></a> 170<a name="index-_002diex"></a> 171<p>Execute a single <small>GDB</small> command before loading the inferior (but 172after loading gdbinit files). 173See <a href="Startup.html#Startup">Startup</a>. 174</p> 175</dd> 176<dt><code>-directory <var>directory</var></code></dt> 177<dt><code>-d <var>directory</var></code></dt> 178<dd><a name="index-_002d_002ddirectory"></a> 179<a name="index-_002dd"></a> 180<p>Add <var>directory</var> to the path to search for source and script files. 181</p> 182</dd> 183<dt><code>-r</code></dt> 184<dt><code>-readnow</code></dt> 185<dd><a name="index-_002d_002dreadnow"></a> 186<a name="index-_002dr"></a> 187<p>Read each symbol file’s entire symbol table immediately, rather than 188the default, which is to read it incrementally as it is needed. 189This makes startup slower, but makes future operations faster. 190</p> 191</dd> 192<dt><code>--readnever</code></dt> 193<dd><a name="g_t_002d_002dreadnever"></a><a name="index-_002d_002dreadnever_002c-command_002dline-option"></a> 194<p>Do not read each symbol file’s symbolic debug information. This makes 195startup faster but at the expense of not being able to perform 196symbolic debugging. DWARF unwind information is also not read, 197meaning backtraces may become incomplete or inaccurate. One use of 198this is when a user simply wants to do the following sequence: attach, 199dump core, detach. Loading the debugging information in this case is 200an unnecessary cause of delay. 201</p></dd> 202</dl> 203 204<hr> 205<div class="header"> 206<p> 207Next: <a href="Mode-Options.html#Mode-Options" accesskey="n" rel="next">Mode Options</a>, Up: <a href="Invoking-GDB.html#Invoking-GDB" accesskey="u" rel="up">Invoking GDB</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> 208</div> 209 210 211 212</body> 213</html> 214