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diff --git a/share/doc/gdb/Asynchronous-and-non_002dstop-modes.html b/share/doc/gdb/Asynchronous-and-non_002dstop-modes.html new file mode 100644 index 0000000..3016d0a --- /dev/null +++ b/share/doc/gdb/Asynchronous-and-non_002dstop-modes.html @@ -0,0 +1,148 @@ +<!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: Asynchronous and non-stop modes</title> + +<meta name="description" content="Debugging with GDB: Asynchronous and non-stop modes"> +<meta name="keywords" content="Debugging with GDB: Asynchronous and non-stop modes"> +<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="GDB_002fMI-General-Design.html#GDB_002fMI-General-Design" rel="up" title="GDB/MI General Design"> +<link href="Thread-groups.html#Thread-groups" rel="next" title="Thread groups"> +<link href="Context-management.html#Context-management" rel="previous" title="Context management"> +<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="Asynchronous-and-non_002dstop-modes"></a> +<div class="header"> +<p> +Next: <a href="Thread-groups.html#Thread-groups" accesskey="n" rel="next">Thread groups</a>, Previous: <a href="Context-management.html#Context-management" accesskey="p" rel="previous">Context management</a>, Up: <a href="GDB_002fMI-General-Design.html#GDB_002fMI-General-Design" accesskey="u" rel="up">GDB/MI General Design</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="Asynchronous-command-execution-and-non_002dstop-mode"></a> +<h4 class="subsection">27.1.2 Asynchronous command execution and non-stop mode</h4> + +<p>On some targets, <small>GDB</small> is capable of processing MI commands +even while the target is running. This is called <em>asynchronous +command execution</em> (see <a href="Background-Execution.html#Background-Execution">Background Execution</a>). The frontend may +specify a preference for asynchronous execution using the +<code>-gdb-set mi-async 1</code> command, which should be emitted before +either running the executable or attaching to the target. After the +frontend has started the executable or attached to the target, it can +find if asynchronous execution is enabled using the +<code>-list-target-features</code> command. +</p> +<dl compact="compact"> +<dd><a name="index-foreground-execution-1"></a> +<a name="index-background-execution-1"></a> +<a name="index-asynchronous-execution-1"></a> +<a name="index-execution_002c-foreground_002c-background-and-asynchronous-1"></a> +<a name="index-set-mi_002dasync"></a> +</dd> +<dt><code>-gdb-set mi-async <span class="roman">[</span>on<span class="roman">|</span>off<span class="roman">]</span></code></dt> +<dd><p>Set whether MI is in asynchronous mode. +</p> +<p>When <code>off</code>, which is the default, MI execution commands (e.g., +<code>-exec-continue</code>) are foreground commands, and <small>GDB</small> waits +for the program to stop before processing further commands. +</p> +<p>When <code>on</code>, MI execution commands are background execution +commands (e.g., <code>-exec-continue</code> becomes the equivalent of the +<code>c&</code> CLI command), and so <small>GDB</small> is capable of processing +MI commands even while the target is running. +</p> +<a name="index-show-mi_002dasync"></a> +</dd> +<dt><code>-gdb-show mi-async</code></dt> +<dd><p>Show whether MI asynchronous mode is enabled. +</p></dd> +</dl> + +<p>Note: In <small>GDB</small> version 7.7 and earlier, this option was called +<code>target-async</code> instead of <code>mi-async</code>, and it had the effect +of both putting MI in asynchronous mode and making CLI background +commands possible. CLI background commands are now always possible +“out of the box” if the target supports them. The old spelling is +kept as a deprecated alias for backwards compatibility. +</p> +<p>Even if <small>GDB</small> can accept a command while target is running, +many commands that access the target do not work when the target is +running. Therefore, asynchronous command execution is most useful +when combined with non-stop mode (see <a href="Non_002dStop-Mode.html#Non_002dStop-Mode">Non-Stop Mode</a>). Then, +it is possible to examine the state of one thread, while other threads +are running. +</p> +<p>When a given thread is running, MI commands that try to access the +target in the context of that thread may not work, or may work only on +some targets. In particular, commands that try to operate on thread’s +stack will not work, on any target. Commands that read memory, or +modify breakpoints, may work or not work, depending on the target. Note +that even commands that operate on global state, such as <code>print</code>, +<code>set</code>, and breakpoint commands, still access the target in the +context of a specific thread, so frontend should try to find a +stopped thread and perform the operation on that thread (using the +‘<samp>--thread</samp>’ option). +</p> +<p>Which commands will work in the context of a running thread is +highly target dependent. However, the two commands +<code>-exec-interrupt</code>, to stop a thread, and <code>-thread-info</code>, +to find the state of a thread, will always work. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Thread-groups.html#Thread-groups" accesskey="n" rel="next">Thread groups</a>, Previous: <a href="Context-management.html#Context-management" accesskey="p" rel="previous">Context management</a>, Up: <a href="GDB_002fMI-General-Design.html#GDB_002fMI-General-Design" accesskey="u" rel="up">GDB/MI General Design</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> |