<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <!-- Copyright (C) 1994-2018 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 no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License". --> <!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ --> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>GDB’s Obsolete Annotations</title> <meta name="description" content="GDB’s Obsolete Annotations"> <meta name="keywords" content="GDB’s Obsolete Annotations"> <meta name="resource-type" content="document"> <meta name="distribution" content="global"> <meta name="Generator" content="makeinfo"> <link href="#Top" rel="start" title="Top"> <link href="#SEC_Contents" rel="contents" title="Table of Contents"> <link href="dir.html#Top" rel="up" title="(dir)"> <style type="text/css"> <!-- a.summary-letter {text-decoration: none} blockquote.indentedblock {margin-right: 0em} blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} blockquote.smallquotation {font-size: smaller} div.display {margin-left: 3.2em} div.example {margin-left: 3.2em} div.lisp {margin-left: 3.2em} div.smalldisplay {margin-left: 3.2em} div.smallexample {margin-left: 3.2em} 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.nolinebreak {white-space: nowrap} span.roman {font-family: initial; font-weight: normal} span.sansserif {font-family: sans-serif; font-weight: normal} ul.no-bullet {list-style: none} --> </style> </head> <body lang="en"> <h1 class="settitle" align="center"><small>GDB</small>’s Obsolete Annotations</h1> <p>This file documents <small>GDB</small>’s obsolete annotations. </p> <p>Copyright © 1994-2018 Free Software Foundation, Inc. </p> <p>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 no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”. </p> <a name="Top"></a> <div class="header"> <p> Next: <a href="#Annotations-Overview" accesskey="n" rel="next">Annotations Overview</a>, Up: <a href="dir.html#Top" accesskey="u" rel="up">(dir)</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="GDB-Annotations"></a> <h1 class="top">GDB Annotations</h1> <p>This document describes the obsolete level two annotation interface implemented in older <small>GDB</small> versions. </p> <table class="menu" border="0" cellspacing="0"> <tr><td align="left" valign="top">• <a href="#Annotations-Overview" accesskey="1">Annotations Overview</a>:</td><td> </td><td align="left" valign="top">What annotations are; the general syntax. </td></tr> <tr><td align="left" valign="top">• <a href="#Limitations" accesskey="2">Limitations</a>:</td><td> </td><td align="left" valign="top">Limitations of the annotation interface. </td></tr> <tr><td align="left" valign="top">• <a href="#Migrating-to-GDB_002fMI" accesskey="3">Migrating to GDB/MI</a>:</td><td> </td><td align="left" valign="top">Migrating to GDB/MI </td></tr> <tr><td align="left" valign="top">• <a href="#Server-Prefix" accesskey="4">Server Prefix</a>:</td><td> </td><td align="left" valign="top">Issuing a command without affecting user state. </td></tr> <tr><td align="left" valign="top">• <a href="#Value-Annotations" accesskey="5">Value Annotations</a>:</td><td> </td><td align="left" valign="top">Values are marked as such. </td></tr> <tr><td align="left" valign="top">• <a href="#Frame-Annotations" accesskey="6">Frame Annotations</a>:</td><td> </td><td align="left" valign="top">Stack frames are annotated. </td></tr> <tr><td align="left" valign="top">• <a href="#Displays" accesskey="7">Displays</a>:</td><td> </td><td align="left" valign="top"><small>GDB</small> can be told to display something periodically. </td></tr> <tr><td align="left" valign="top">• <a href="#Prompting" accesskey="8">Prompting</a>:</td><td> </td><td align="left" valign="top">Annotations marking <small>GDB</small>’s need for input. </td></tr> <tr><td align="left" valign="top">• <a href="#Errors" accesskey="9">Errors</a>:</td><td> </td><td align="left" valign="top">Annotations for error messages. </td></tr> <tr><td align="left" valign="top">• <a href="#Breakpoint-Info">Breakpoint Info</a>:</td><td> </td><td align="left" valign="top">Information on breakpoints. </td></tr> <tr><td align="left" valign="top">• <a href="#Invalidation">Invalidation</a>:</td><td> </td><td align="left" valign="top">Some annotations describe things now invalid. </td></tr> <tr><td align="left" valign="top">• <a href="#Annotations-for-Running">Annotations for Running</a>:</td><td> </td><td align="left" valign="top"> Whether the program is running, how it stopped, etc. </td></tr> <tr><td align="left" valign="top">• <a href="#Source-Annotations">Source Annotations</a>:</td><td> </td><td align="left" valign="top">Annotations describing source code. </td></tr> <tr><td align="left" valign="top">• <a href="#Multi_002dthreaded-Apps">Multi-threaded Apps</a>:</td><td> </td><td align="left" valign="top">An annotation that reports multi-threadedness. </td></tr> <tr><th colspan="3" align="left" valign="top"><pre class="menu-comment"> </pre></th></tr><tr><td align="left" valign="top">• <a href="#GNU-Free-Documentation-License">GNU Free Documentation License</a>:</td><td> </td><td align="left" valign="top"> </td></tr> </table> <a name="SEC_Contents"></a> <h2 class="contents-heading">Table of Contents</h2> <div class="contents"> <ul class="no-bullet"> <li><a name="toc-What-is-an-Annotation_003f" href="#Annotations-Overview">1 What is an Annotation?</a></li> <li><a name="toc-Limitations-of-the-Annotation-Interface" href="#Limitations">2 Limitations of the Annotation Interface</a> <ul class="no-bullet"> <li><a name="toc-Dependant-on-CLI-output" href="#Dependant-on-CLI-output">2.1 Dependant on <small>CLI</small> output</a></li> <li><a name="toc-Scalability" href="#Scalability">2.2 Scalability</a></li> <li><a name="toc-Correctness" href="#Correctness">2.3 Correctness</a></li> <li><a name="toc-Reliability" href="#Reliability">2.4 Reliability</a></li> <li><a name="toc-Maintainability" href="#Maintainability">2.5 Maintainability</a></li> </ul></li> <li><a name="toc-Migrating-to-GDB_002fMI-1" href="#Migrating-to-GDB_002fMI">3 Migrating to <small>GDB/MI</small></a></li> <li><a name="toc-The-Server-Prefix" href="#Server-Prefix">4 The Server Prefix</a></li> <li><a name="toc-Values" href="#Value-Annotations">5 Values</a></li> <li><a name="toc-Frames" href="#Frame-Annotations">6 Frames</a></li> <li><a name="toc-Displays-1" href="#Displays">7 Displays</a></li> <li><a name="toc-Annotation-for-GDB-Input" href="#Prompting">8 Annotation for <small>GDB</small> Input</a></li> <li><a name="toc-Errors-1" href="#Errors">9 Errors</a></li> <li><a name="toc-Information-on-Breakpoints" href="#Breakpoint-Info">10 Information on Breakpoints</a></li> <li><a name="toc-Invalidation-Notices" href="#Invalidation">11 Invalidation Notices</a></li> <li><a name="toc-Running-the-Program" href="#Annotations-for-Running">12 Running the Program</a></li> <li><a name="toc-Displaying-Source" href="#Source-Annotations">13 Displaying Source</a></li> <li><a name="toc-Multi_002dthreaded-Applications" href="#Multi_002dthreaded-Apps">14 Multi-threaded Applications</a></li> <li><a name="toc-GNU-Free-Documentation-License-1" href="#GNU-Free-Documentation-License">Appendix A GNU Free Documentation License</a></li> </ul> </div> <hr> <a name="Annotations-Overview"></a> <div class="header"> <p> Next: <a href="#Limitations" accesskey="n" rel="next">Limitations</a>, Previous: <a href="#Top" accesskey="p" rel="prev">Top</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="What-is-an-Annotation_003f"></a> <h2 class="chapter">1 What is an Annotation?</h2> <a name="index-annotations"></a> <p>To produce obsolete level two annotations, start <small>GDB</small> with the <code>--annotate=2</code> option. </p> <p>Annotations start with a newline character, two ‘<samp>control-z</samp>’ characters, and the name of the annotation. If there is no additional information associated with this annotation, the name of the annotation is followed immediately by a newline. If there is additional information, the name of the annotation is followed by a space, the additional information, and a newline. The additional information cannot contain newline characters. </p> <p>Any output not beginning with a newline and two ‘<samp>control-z</samp>’ characters denotes literal output from <small>GDB</small>. Currently there is no need for <small>GDB</small> to output a newline followed by two ‘<samp>control-z</samp>’ characters, but if there was such a need, the annotations could be extended with an ‘<samp>escape</samp>’ annotation which means those three characters as output. </p> <p>A simple example of starting up <small>GDB</small> with annotations is: </p> <div class="smallexample"> <pre class="smallexample">$ gdb --annotate=2 GNU GDB 5.0 Copyright 2000 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "sparc-sun-sunos4.1.3" ^Z^Zpre-prompt (gdb) ^Z^Zprompt quit ^Z^Zpost-prompt $ </pre></div> <p>Here ‘<samp>quit</samp>’ is input to <small>GDB</small>; the rest is output from <small>GDB</small>. The three lines beginning ‘<samp>^Z^Z</samp>’ (where ‘<samp>^Z</samp>’ denotes a ‘<samp>control-z</samp>’ character) are annotations; the rest is output from <small>GDB</small>. </p> <hr> <a name="Limitations"></a> <div class="header"> <p> Next: <a href="#Migrating-to-GDB_002fMI" accesskey="n" rel="next">Migrating to GDB/MI</a>, Previous: <a href="#Annotations-Overview" accesskey="p" rel="prev">Annotations Overview</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Limitations-of-the-Annotation-Interface"></a> <h2 class="chapter">2 Limitations of the Annotation Interface</h2> <p>The level two annotations mechanism is known to have a number of technical and architectural limitations. As a consequence, in 2001, with the release of <small>GDB</small> 5.1 and the addition of <small>GDB/MI</small>, the annotation interface was marked as deprecated. </p> <p>This chapter discusses the known problems. </p> <a name="Dependant-on-CLI-output"></a> <h3 class="section">2.1 Dependant on <small>CLI</small> output</h3> <p>The annotation interface works by interspersing markups with <small>GDB</small> normal command-line interpreter output. Unfortunately, this makes the annotation client dependant on not just the annotations, but also the <small>CLI</small> output. This is because the client is forced to assume that specific <small>GDB</small> commands provide specific information. Any change to <small>GDB</small>’s <small>CLI</small> output modifies or removes that information and, consequently, likely breaks the client. </p> <p>Since the <small>GDB/MI</small> output is independent of the <small>CLI</small>, it does not have this problem. </p> <a name="Scalability"></a> <h3 class="section">2.2 Scalability</h3> <p>The annotation interface relies on value annotations (see <a href="#Value-Annotations">Value Annotations</a>) and the display mechanism as a way of obtaining up-to-date value information. These mechanisms are not scalable. </p> <p>In a graphical environment, where many values can be displayed simultaneously, a serious performance problem occurs when the client tries to first extract from <small>GDB</small>, and then re-display, all those values. The client should instead only request and update the values that changed. </p> <p>The <small>GDB/MI</small> Variable Objects provide just that mechanism. </p> <a name="Correctness"></a> <h3 class="section">2.3 Correctness</h3> <p>The annotation interface assumes that a variable’s value can only be changed when the target is running. This assumption is not correct. A single assignment to a single variable can result in the entire target, and all displayed values, needing an update. </p> <p>The <small>GDB/MI</small> Variable Objects include a mechanism for efficiently reporting such changes. </p> <a name="Reliability"></a> <h3 class="section">2.4 Reliability</h3> <p>The <small>GDB/MI</small> interface includes a dedicated test directory (<samp>gdb/gdb.mi</samp>), and any addition or fix to <small>GDB/MI</small> must include testsuite changes. </p> <a name="Maintainability"></a> <h3 class="section">2.5 Maintainability</h3> <p>The annotation mechanism was implemented by interspersing <small>CLI</small> print statements with various annotations. As a consequence, any <small>CLI</small> output change can alter the annotation output. </p> <p>Since the <small>GDB/MI</small> output is independent of the <small>CLI</small>, and the <small>GDB/MI</small> is increasingly implemented independent of the <small>CLI</small> code, its long term maintenance is much easier. </p> <hr> <a name="Migrating-to-GDB_002fMI"></a> <div class="header"> <p> Next: <a href="#Server-Prefix" accesskey="n" rel="next">Server Prefix</a>, Previous: <a href="#Limitations" accesskey="p" rel="prev">Limitations</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Migrating-to-GDB_002fMI-1"></a> <h2 class="chapter">3 Migrating to <small>GDB/MI</small></h2> <p>By using the ‘<samp>interp mi</samp>’ command, it is possible for annotation clients to invoke <small>GDB/MI</small> commands, and hence access the <small>GDB/MI</small>. By doing this, existing annotation clients have a migration path from this obsolete interface to <small>GDB/MI</small>. </p> <hr> <a name="Server-Prefix"></a> <div class="header"> <p> Next: <a href="#Value-Annotations" accesskey="n" rel="next">Value Annotations</a>, Previous: <a href="#Migrating-to-GDB_002fMI" accesskey="p" rel="prev">Migrating to GDB/MI</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="The-Server-Prefix"></a> <h2 class="chapter">4 The Server Prefix</h2> <a name="index-server-prefix-for-annotations"></a> <p>To issue a command to <small>GDB</small> without affecting certain aspects of the state which is seen by users, prefix it with ‘<samp>server </samp>’. This means that this command will not affect the command history, nor will it affect <small>GDB</small>’s notion of which command to repeat if <tt class="key">RET</tt> is pressed on a line by itself. </p> <p>The server prefix does not affect the recording of values into the value history; to print a value without recording it into the value history, use the <code>output</code> command instead of the <code>print</code> command. </p> <hr> <a name="Value-Annotations"></a> <div class="header"> <p> Next: <a href="#Frame-Annotations" accesskey="n" rel="next">Frame Annotations</a>, Previous: <a href="#Server-Prefix" accesskey="p" rel="prev">Server Prefix</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Values"></a> <h2 class="chapter">5 Values</h2> <p><em>Value Annotations have been removed. <small>GDB/MI</small> instead provides Variable Objects.</em> </p> <a name="index-annotations-for-values"></a> <p>When a value is printed in various contexts, <small>GDB</small> uses annotations to delimit the value from the surrounding text. </p> <a name="index-value_002dhistory_002dbegin"></a> <a name="index-value_002dhistory_002dvalue"></a> <a name="index-value_002dhistory_002dend"></a> <p>If a value is printed using <code>print</code> and added to the value history, the annotation looks like </p> <div class="smallexample"> <pre class="smallexample">^Z^Zvalue-history-begin <var>history-number</var> <var>value-flags</var> <var>history-string</var> ^Z^Zvalue-history-value <var>the-value</var> ^Z^Zvalue-history-end </pre></div> <p>where <var>history-number</var> is the number it is getting in the value history, <var>history-string</var> is a string, such as ‘<samp>$5 = </samp>’, which introduces the value to the user, <var>the-value</var> is the output corresponding to the value itself, and <var>value-flags</var> is ‘<samp>*</samp>’ for a value which can be dereferenced and ‘<samp>-</samp>’ for a value which cannot. </p> <a name="index-value_002dbegin"></a> <a name="index-value_002dend"></a> <p>If the value is not added to the value history (it is an invalid float or it is printed with the <code>output</code> command), the annotation is similar: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zvalue-begin <var>value-flags</var> <var>the-value</var> ^Z^Zvalue-end </pre></div> <a name="index-arg_002dbegin"></a> <a name="index-arg_002dname_002dend"></a> <a name="index-arg_002dvalue"></a> <a name="index-arg_002dend"></a> <p>When <small>GDB</small> prints an argument to a function (for example, in the output from the <code>backtrace</code> command), it annotates it as follows: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zarg-begin <var>argument-name</var> ^Z^Zarg-name-end <var>separator-string</var> ^Z^Zarg-value <var>value-flags</var> <var>the-value</var> ^Z^Zarg-end </pre></div> <p>where <var>argument-name</var> is the name of the argument, <var>separator-string</var> is text which separates the name from the value for the user’s benefit (such as ‘<samp>=</samp>’), and <var>value-flags</var> and <var>the-value</var> have the same meanings as in a <code>value-history-begin</code> annotation. </p> <a name="index-field_002dbegin"></a> <a name="index-field_002dname_002dend"></a> <a name="index-field_002dvalue"></a> <a name="index-field_002dend"></a> <p>When printing a structure, <small>GDB</small> annotates it as follows: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zfield-begin <var>value-flags</var> <var>field-name</var> ^Z^Zfield-name-end <var>separator-string</var> ^Z^Zfield-value <var>the-value</var> ^Z^Zfield-end </pre></div> <p>where <var>field-name</var> is the name of the field, <var>separator-string</var> is text which separates the name from the value for the user’s benefit (such as ‘<samp>=</samp>’), and <var>value-flags</var> and <var>the-value</var> have the same meanings as in a <code>value-history-begin</code> annotation. </p> <p>When printing an array, <small>GDB</small> annotates it as follows: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zarray-section-begin <var>array-index</var> <var>value-flags</var> </pre></div> <p>where <var>array-index</var> is the index of the first element being annotated and <var>value-flags</var> has the same meaning as in a <code>value-history-begin</code> annotation. This is followed by any number of elements, where is element can be either a single element: </p> <a name="index-elt"></a> <div class="smallexample"> <pre class="smallexample">‘<samp>,</samp>’ <var>whitespace</var> ; <span class="roman">omitted for the first element</span> <var>the-value</var> ^Z^Zelt </pre></div> <p>or a repeated element </p> <a name="index-elt_002drep"></a> <a name="index-elt_002drep_002dend"></a> <div class="smallexample"> <pre class="smallexample">‘<samp>,</samp>’ <var>whitespace</var> ; <span class="roman">omitted for the first element</span> <var>the-value</var> ^Z^Zelt-rep <var>number-of-repetitions</var> <var>repetition-string</var> ^Z^Zelt-rep-end </pre></div> <p>In both cases, <var>the-value</var> is the output for the value of the element and <var>whitespace</var> can contain spaces, tabs, and newlines. In the repeated case, <var>number-of-repetitions</var> is the number of consecutive array elements which contain that value, and <var>repetition-string</var> is a string which is designed to convey to the user that repetition is being depicted. </p> <a name="index-array_002dsection_002dend"></a> <p>Once all the array elements have been output, the array annotation is ended with </p> <div class="smallexample"> <pre class="smallexample">^Z^Zarray-section-end </pre></div> <hr> <a name="Frame-Annotations"></a> <div class="header"> <p> Next: <a href="#Displays" accesskey="n" rel="next">Displays</a>, Previous: <a href="#Value-Annotations" accesskey="p" rel="prev">Value Annotations</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Frames"></a> <h2 class="chapter">6 Frames</h2> <p><em>Value Annotations have been removed. <small>GDB/MI</small> instead provides a number of frame commands.</em> </p> <p><em>Frame annotations are no longer available. The <small>GDB/MI</small> provides ‘<samp>-stack-list-arguments</samp>’, ‘<samp>-stack-list-locals</samp>’, and ‘<samp>-stack-list-frames</samp>’ commands.</em> </p> <a name="index-annotations-for-frames"></a> <p>Whenever <small>GDB</small> prints a frame, it annotates it. For example, this applies to frames printed when <small>GDB</small> stops, output from commands such as <code>backtrace</code> or <code>up</code>, etc. </p> <a name="index-frame_002dbegin"></a> <p>The frame annotation begins with </p> <div class="smallexample"> <pre class="smallexample">^Z^Zframe-begin <var>level</var> <var>address</var> <var>level-string</var> </pre></div> <p>where <var>level</var> is the number of the frame (0 is the innermost frame, and other frames have positive numbers), <var>address</var> is the address of the code executing in that frame, and <var>level-string</var> is a string designed to convey the level to the user. <var>address</var> is in the form ‘<samp>0x</samp>’ followed by one or more lowercase hex digits (note that this does not depend on the language). The frame ends with </p> <a name="index-frame_002dend"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zframe-end </pre></div> <p>Between these annotations is the main body of the frame, which can consist of </p> <ul> <li> <a name="index-function_002dcall"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zfunction-call <var>function-call-string</var> </pre></div> where <var>function-call-string</var> is text designed to convey to the user that this frame is associated with a function call made by <small>GDB</small> to a function in the program being debugged. </li><li> <a name="index-signal_002dhandler_002dcaller"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zsignal-handler-caller <var>signal-handler-caller-string</var> </pre></div> where <var>signal-handler-caller-string</var> is text designed to convey to the user that this frame is associated with whatever mechanism is used by this operating system to call a signal handler (it is the frame which calls the signal handler, not the frame for the signal handler itself). </li><li> A normal frame. <a name="index-frame_002daddress"></a> <a name="index-frame_002daddress_002dend"></a> <p>This can optionally (depending on whether this is thought of as interesting information for the user to see) begin with </p> <div class="smallexample"> <pre class="smallexample">^Z^Zframe-address <var>address</var> ^Z^Zframe-address-end <var>separator-string</var> </pre></div> <p>where <var>address</var> is the address executing in the frame (the same address as in the <code>frame-begin</code> annotation, but printed in a form which is intended for user consumption—in particular, the syntax varies depending on the language), and <var>separator-string</var> is a string intended to separate this address from what follows for the user’s benefit. </p> <a name="index-frame_002dfunction_002dname"></a> <a name="index-frame_002dargs"></a> <p>Then comes </p> <div class="smallexample"> <pre class="smallexample">^Z^Zframe-function-name <var>function-name</var> ^Z^Zframe-args <var>arguments</var> </pre></div> <p>where <var>function-name</var> is the name of the function executing in the frame, or ‘<samp>??</samp>’ if not known, and <var>arguments</var> are the arguments to the frame, with parentheses around them (each argument is annotated individually as well, see <a href="#Value-Annotations">Value Annotations</a>). </p> <a name="index-frame_002dsource_002dbegin"></a> <a name="index-frame_002dsource_002dfile"></a> <a name="index-frame_002dsource_002dfile_002dend"></a> <a name="index-frame_002dsource_002dline"></a> <a name="index-frame_002dsource_002dend"></a> <p>If source information is available, a reference to it is then printed: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zframe-source-begin <var>source-intro-string</var> ^Z^Zframe-source-file <var>filename</var> ^Z^Zframe-source-file-end : ^Z^Zframe-source-line <var>line-number</var> ^Z^Zframe-source-end </pre></div> <p>where <var>source-intro-string</var> separates for the user’s benefit the reference from the text which precedes it, <var>filename</var> is the name of the source file, and <var>line-number</var> is the line number within that file (the first line is line 1). </p> <a name="index-frame_002dwhere"></a> <p>If <small>GDB</small> prints some information about where the frame is from (which library, which load segment, etc.; currently only done on the RS/6000), it is annotated with </p> <div class="smallexample"> <pre class="smallexample">^Z^Zframe-where <var>information</var> </pre></div> <p>Then, if source is to actually be displayed for this frame (for example, this is not true for output from the <code>backtrace</code> command), then a <code>source</code> annotation (see <a href="#Source-Annotations">Source Annotations</a>) is displayed. Unlike most annotations, this is output instead of the normal text which would be output, not in addition. </p></li></ul> <hr> <a name="Displays"></a> <div class="header"> <p> Next: <a href="#Prompting" accesskey="n" rel="next">Prompting</a>, Previous: <a href="#Frame-Annotations" accesskey="p" rel="prev">Frame Annotations</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Displays-1"></a> <h2 class="chapter">7 Displays</h2> <p><em>Display Annotations have been removed. <small>GDB/MI</small> instead provides Variable Objects.</em> </p> <a name="index-display_002dbegin"></a> <a name="index-display_002dnumber_002dend"></a> <a name="index-display_002dformat"></a> <a name="index-display_002dexpression"></a> <a name="index-display_002dexpression_002dend"></a> <a name="index-display_002dvalue"></a> <a name="index-display_002dend"></a> <a name="index-annotations-for-display"></a> <p>When <small>GDB</small> is told to display something using the <code>display</code> command, the results of the display are annotated: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zdisplay-begin <var>number</var> ^Z^Zdisplay-number-end <var>number-separator</var> ^Z^Zdisplay-format <var>format</var> ^Z^Zdisplay-expression <var>expression</var> ^Z^Zdisplay-expression-end <var>expression-separator</var> ^Z^Zdisplay-value <var>value</var> ^Z^Zdisplay-end </pre></div> <p>where <var>number</var> is the number of the display, <var>number-separator</var> is intended to separate the number from what follows for the user, <var>format</var> includes information such as the size, format, or other information about how the value is being displayed, <var>expression</var> is the expression being displayed, <var>expression-separator</var> is intended to separate the expression from the text that follows for the user, and <var>value</var> is the actual value being displayed. </p> <hr> <a name="Prompting"></a> <div class="header"> <p> Next: <a href="#Errors" accesskey="n" rel="next">Errors</a>, Previous: <a href="#Displays" accesskey="p" rel="prev">Displays</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Annotation-for-GDB-Input"></a> <h2 class="chapter">8 Annotation for <small>GDB</small> Input</h2> <a name="index-annotations-for-prompts"></a> <p>When <small>GDB</small> prompts for input, it annotates this fact so it is possible to know when to send output, when the output from a given command is over, etc. </p> <p>Different kinds of input each have a different <em>input type</em>. Each input type has three annotations: a <code>pre-</code> annotation, which denotes the beginning of any prompt which is being output, a plain annotation, which denotes the end of the prompt, and then a <code>post-</code> annotation which denotes the end of any echo which may (or may not) be associated with the input. For example, the <code>prompt</code> input type features the following annotations: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zpre-prompt ^Z^Zprompt ^Z^Zpost-prompt </pre></div> <p>The input types are </p> <dl compact="compact"> <dd><a name="index-pre_002dprompt"></a> <a name="index-prompt"></a> <a name="index-post_002dprompt"></a> </dd> <dt><code>prompt</code></dt> <dd><p>When <small>GDB</small> is prompting for a command (the main <small>GDB</small> prompt). </p> <a name="index-pre_002dcommands"></a> <a name="index-commands"></a> <a name="index-post_002dcommands"></a> </dd> <dt><code>commands</code></dt> <dd><p>When <small>GDB</small> prompts for a set of commands, like in the <code>commands</code> command. The annotations are repeated for each command which is input. </p> <a name="index-pre_002doverload_002dchoice"></a> <a name="index-overload_002dchoice"></a> <a name="index-post_002doverload_002dchoice"></a> </dd> <dt><code>overload-choice</code></dt> <dd><p>When <small>GDB</small> wants the user to select between various overloaded functions. </p> <a name="index-pre_002dquery"></a> <a name="index-query"></a> <a name="index-post_002dquery"></a> </dd> <dt><code>query</code></dt> <dd><p>When <small>GDB</small> wants the user to confirm a potentially dangerous operation. </p> <a name="index-pre_002dprompt_002dfor_002dcontinue"></a> <a name="index-prompt_002dfor_002dcontinue"></a> <a name="index-post_002dprompt_002dfor_002dcontinue"></a> </dd> <dt><code>prompt-for-continue</code></dt> <dd><p>When <small>GDB</small> is asking the user to press return to continue. Note: Don’t expect this to work well; instead use <code>set height 0</code> to disable prompting. This is because the counting of lines is buggy in the presence of annotations. </p></dd> </dl> <hr> <a name="Errors"></a> <div class="header"> <p> Next: <a href="#Breakpoint-Info" accesskey="n" rel="next">Breakpoint Info</a>, Previous: <a href="#Prompting" accesskey="p" rel="prev">Prompting</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Errors-1"></a> <h2 class="chapter">9 Errors</h2> <a name="index-annotations-for-errors_002c-warnings-and-interrupts"></a> <a name="index-quit"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zquit </pre></div> <p>This annotation occurs right before <small>GDB</small> responds to an interrupt. </p> <a name="index-error"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zerror </pre></div> <p>This annotation occurs right before <small>GDB</small> responds to an error. </p> <p>Quit and error annotations indicate that any annotations which <small>GDB</small> was in the middle of may end abruptly. For example, if a <code>value-history-begin</code> annotation is followed by a <code>error</code>, one cannot expect to receive the matching <code>value-history-end</code>. One cannot expect not to receive it either, however; an error annotation does not necessarily mean that <small>GDB</small> is immediately returning all the way to the top level. </p> <a name="index-error_002dbegin"></a> <p>A quit or error annotation may be preceded by </p> <div class="smallexample"> <pre class="smallexample">^Z^Zerror-begin </pre></div> <p>Any output between that and the quit or error annotation is the error message. </p> <p>Warning messages are not yet annotated. </p> <hr> <a name="Breakpoint-Info"></a> <div class="header"> <p> Next: <a href="#Invalidation" accesskey="n" rel="next">Invalidation</a>, Previous: <a href="#Errors" accesskey="p" rel="prev">Errors</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Information-on-Breakpoints"></a> <h2 class="chapter">10 Information on Breakpoints</h2> <p><em>Breakpoint Annotations have been removed. <small>GDB/MI</small> instead provides breakpoint commands.</em> </p> <a name="index-annotations-for-breakpoints"></a> <p>The output from the <code>info breakpoints</code> command is annotated as follows: </p> <a name="index-breakpoints_002dheaders"></a> <a name="index-breakpoints_002dtable"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zbreakpoints-headers <var>header-entry</var> ^Z^Zbreakpoints-table </pre></div> <p>where <var>header-entry</var> has the same syntax as an entry (see below) but instead of containing data, it contains strings which are intended to convey the meaning of each field to the user. This is followed by any number of entries. If a field does not apply for this entry, it is omitted. Fields may contain trailing whitespace. Each entry consists of: </p> <a name="index-record"></a> <a name="index-field"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zrecord ^Z^Zfield 0 <var>number</var> ^Z^Zfield 1 <var>type</var> ^Z^Zfield 2 <var>disposition</var> ^Z^Zfield 3 <var>enable</var> ^Z^Zfield 4 <var>address</var> ^Z^Zfield 5 <var>what</var> ^Z^Zfield 6 <var>frame</var> ^Z^Zfield 7 <var>condition</var> ^Z^Zfield 8 <var>ignore-count</var> ^Z^Zfield 9 <var>commands</var> </pre></div> <p>Note that <var>address</var> is intended for user consumption—the syntax varies depending on the language. </p> <p>The output ends with </p> <a name="index-breakpoints_002dtable_002dend"></a> <div class="smallexample"> <pre class="smallexample">^Z^Zbreakpoints-table-end </pre></div> <hr> <a name="Invalidation"></a> <div class="header"> <p> Next: <a href="#Annotations-for-Running" accesskey="n" rel="next">Annotations for Running</a>, Previous: <a href="#Breakpoint-Info" accesskey="p" rel="prev">Breakpoint Info</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Invalidation-Notices"></a> <h2 class="chapter">11 Invalidation Notices</h2> <a name="index-annotations-for-invalidation-messages"></a> <p>The following annotations say that certain pieces of state may have changed. </p> <dl compact="compact"> <dd><a name="index-frames_002dinvalid"></a> </dd> <dt><code>^Z^Zframes-invalid</code></dt> <dd> <p>The frames (for example, output from the <code>backtrace</code> command) may have changed. </p> <a name="index-breakpoints_002dinvalid"></a> </dd> <dt><code>^Z^Zbreakpoints-invalid</code></dt> <dd> <p>The breakpoints may have changed. For example, the user just added or deleted a breakpoint. </p></dd> </dl> <hr> <a name="Annotations-for-Running"></a> <div class="header"> <p> Next: <a href="#Source-Annotations" accesskey="n" rel="next">Source Annotations</a>, Previous: <a href="#Invalidation" accesskey="p" rel="prev">Invalidation</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Running-the-Program"></a> <h2 class="chapter">12 Running the Program</h2> <a name="index-annotations-for-running-programs"></a> <a name="index-starting"></a> <a name="index-stopping"></a> <p>When the program starts executing due to a <small>GDB</small> command such as <code>step</code> or <code>continue</code>, </p> <div class="smallexample"> <pre class="smallexample">^Z^Zstarting </pre></div> <p>is output. When the program stops, </p> <div class="smallexample"> <pre class="smallexample">^Z^Zstopped </pre></div> <p>is output. Before the <code>stopped</code> annotation, a variety of annotations describe how the program stopped. </p> <dl compact="compact"> <dd><a name="index-exited"></a> </dd> <dt><code>^Z^Zexited <var>exit-status</var></code></dt> <dd><p>The program exited, and <var>exit-status</var> is the exit status (zero for successful exit, otherwise nonzero). </p> <a name="index-signalled"></a> <a name="index-signal_002dname"></a> <a name="index-signal_002dname_002dend"></a> <a name="index-signal_002dstring"></a> <a name="index-signal_002dstring_002dend"></a> </dd> <dt><code>^Z^Zsignalled</code></dt> <dd><p>The program exited with a signal. After the <code>^Z^Zsignalled</code>, the annotation continues: </p> <div class="smallexample"> <pre class="smallexample"><var>intro-text</var> ^Z^Zsignal-name <var>name</var> ^Z^Zsignal-name-end <var>middle-text</var> ^Z^Zsignal-string <var>string</var> ^Z^Zsignal-string-end <var>end-text</var> </pre></div> <p>where <var>name</var> is the name of the signal, such as <code>SIGILL</code> or <code>SIGSEGV</code>, and <var>string</var> is the explanation of the signal, such as <code>Illegal Instruction</code> or <code>Segmentation fault</code>. <var>intro-text</var>, <var>middle-text</var>, and <var>end-text</var> are for the user’s benefit and have no particular format. </p> <a name="index-signal"></a> </dd> <dt><code>^Z^Zsignal</code></dt> <dd><p>The syntax of this annotation is just like <code>signalled</code>, but <small>GDB</small> is just saying that the program received the signal, not that it was terminated with it. </p> <a name="index-breakpoint"></a> </dd> <dt><code>^Z^Zbreakpoint <var>number</var></code></dt> <dd><p>The program hit breakpoint number <var>number</var>. </p> <a name="index-watchpoint"></a> </dd> <dt><code>^Z^Zwatchpoint <var>number</var></code></dt> <dd><p>The program hit watchpoint number <var>number</var>. </p></dd> </dl> <hr> <a name="Source-Annotations"></a> <div class="header"> <p> Next: <a href="#Multi_002dthreaded-Apps" accesskey="n" rel="next">Multi-threaded Apps</a>, Previous: <a href="#Annotations-for-Running" accesskey="p" rel="prev">Annotations for Running</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Displaying-Source"></a> <h2 class="chapter">13 Displaying Source</h2> <a name="index-annotations-for-source-display"></a> <a name="index-source"></a> <p>The following annotation is used instead of displaying source code: </p> <div class="smallexample"> <pre class="smallexample">^Z^Zsource <var>filename</var>:<var>line</var>:<var>character</var>:<var>middle</var>:<var>addr</var> </pre></div> <p>where <var>filename</var> is an absolute file name indicating which source file, <var>line</var> is the line number within that file (where 1 is the first line in the file), <var>character</var> is the character position within the file (where 0 is the first character in the file) (for most debug formats this will necessarily point to the beginning of a line), <var>middle</var> is ‘<samp>middle</samp>’ if <var>addr</var> is in the middle of the line, or ‘<samp>beg</samp>’ if <var>addr</var> is at the beginning of the line, and <var>addr</var> is the address in the target program associated with the source which is being displayed. <var>addr</var> is in the form ‘<samp>0x</samp>’ followed by one or more lowercase hex digits (note that this does not depend on the language). </p> <hr> <a name="Multi_002dthreaded-Apps"></a> <div class="header"> <p> Next: <a href="#GNU-Free-Documentation-License" accesskey="n" rel="next">GNU Free Documentation License</a>, Previous: <a href="#Source-Annotations" accesskey="p" rel="prev">Source Annotations</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="Multi_002dthreaded-Applications"></a> <h2 class="chapter">14 Multi-threaded Applications</h2> <a name="index-annotations-for-multi_002dthreaded-apps"></a> <p>The following annotations report thread related changes of state. </p> <dl compact="compact"> <dd><a name="index-new_002dthread_002c-annotation"></a> </dd> <dt><code>^Z^Znew-thread</code></dt> <dd> <p>This annotation is issued once for each thread that is created apart from the main thread, which is not reported. </p> <a name="index-thread_002dchanged_002c-annotation"></a> </dd> <dt><code>^Z^Zthread-changed</code></dt> <dd> <p>The selected thread has changed. This may occur at the request of the user with the <code>thread</code> command, or as a result of execution, e.g., another thread hits a breakpoint. </p> </dd> </dl> <hr> <a name="GNU-Free-Documentation-License"></a> <div class="header"> <p> Previous: <a href="#Multi_002dthreaded-Apps" accesskey="p" rel="prev">Multi-threaded Apps</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> [<a href="#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p> </div> <a name="GNU-Free-Documentation-License-1"></a> <h2 class="appendix">Appendix A GNU Free Documentation License</h2> <div align="center">Version 1.3, 3 November 2008 </div> <div class="display"> <pre class="display">Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. <a href="http://fsf.org/">http://fsf.org/</a> Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. </pre></div> <ol start="0"> <li> PREAMBLE <p>The purpose of this License is to make a manual, textbook, or other functional and useful document <em>free</em> in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. 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These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License. </p> </li><li> VERBATIM COPYING <p>You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3. </p> <p>You may also lend copies, under the same conditions stated above, and you may publicly display copies. </p> </li><li> COPYING IN QUANTITY <p>If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects. </p> <p>If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages. </p> <p>If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public. </p> <p>It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document. </p> </li><li> MODIFICATIONS <p>You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version: </p> <ol type="A" start="1"> <li> Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission. </li><li> List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement. </li><li> State on the Title page the name of the publisher of the Modified Version, as the publisher. </li><li> Preserve all the copyright notices of the Document. </li><li> Add an appropriate copyright notice for your modifications adjacent to the other copyright notices. </li><li> Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below. </li><li> Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice. </li><li> Include an unaltered copy of this License. </li><li> Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence. </li><li> Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission. </li><li> For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein. </li><li> Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles. </li><li> Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version. </li><li> Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section. </li><li> Preserve any Warranty Disclaimers. </li></ol> <p>If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles. </p> <p>You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard. </p> <p>You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one. </p> <p>The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version. </p> </li><li> COMBINING DOCUMENTS <p>You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers. </p> <p>The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work. </p> <p>In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.” </p> </li><li> COLLECTIONS OF DOCUMENTS <p>You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects. </p> <p>You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document. </p> </li><li> AGGREGATION WITH INDEPENDENT WORKS <p>A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document. </p> <p>If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate. </p> </li><li> TRANSLATION <p>Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail. </p> <p>If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title. </p> </li><li> TERMINATION <p>You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License. </p> <p>However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation. </p> <p>Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice. </p> <p>Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it. </p> </li><li> FUTURE REVISIONS OF THIS LICENSE <p>The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See <a href="http://www.gnu.org/copyleft/">http://www.gnu.org/copyleft/</a>. </p> <p>Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document. </p> </li><li> RELICENSING <p>“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site. </p> <p>“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization. </p> <p>“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document. </p> <p>An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008. </p> <p>The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing. </p> </li></ol> <a name="ADDENDUM_003a-How-to-use-this-License-for-your-documents"></a> <h3 class="heading">ADDENDUM: How to use this License for your documents</h3> <p>To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page: </p> <div class="smallexample"> <pre class="smallexample"> Copyright (C) <var>year</var> <var>your name</var>. 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 no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. </pre></div> <p>If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this: </p> <div class="smallexample"> <pre class="smallexample"> with the Invariant Sections being <var>list their titles</var>, with the Front-Cover Texts being <var>list</var>, and with the Back-Cover Texts being <var>list</var>. </pre></div> <p>If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation. </p> <p>If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software. </p> <hr> </body> </html>