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diff --git a/share/doc/gdb/Trace-State-Variables.html b/share/doc/gdb/Trace-State-Variables.html new file mode 100644 index 0000000..deabb36 --- /dev/null +++ b/share/doc/gdb/Trace-State-Variables.html @@ -0,0 +1,134 @@ +<!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: Trace State Variables</title> + +<meta name="description" content="Debugging with GDB: Trace State Variables"> +<meta name="keywords" content="Debugging with GDB: Trace State Variables"> +<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="Set-Tracepoints.html#Set-Tracepoints" rel="up" title="Set Tracepoints"> +<link href="Tracepoint-Actions.html#Tracepoint-Actions" rel="next" title="Tracepoint Actions"> +<link href="Tracepoint-Conditions.html#Tracepoint-Conditions" rel="previous" title="Tracepoint Conditions"> +<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="Trace-State-Variables"></a> +<div class="header"> +<p> +Next: <a href="Tracepoint-Actions.html#Tracepoint-Actions" accesskey="n" rel="next">Tracepoint Actions</a>, Previous: <a href="Tracepoint-Conditions.html#Tracepoint-Conditions" accesskey="p" rel="previous">Tracepoint Conditions</a>, Up: <a href="Set-Tracepoints.html#Set-Tracepoints" accesskey="u" rel="up">Set Tracepoints</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="Trace-State-Variables-1"></a> +<h4 class="subsection">13.1.5 Trace State Variables</h4> +<a name="index-trace-state-variables"></a> + +<p>A <em>trace state variable</em> is a special type of variable that is +created and managed by target-side code. The syntax is the same as +that for GDB’s convenience variables (a string prefixed with “$”), +but they are stored on the target. They must be created explicitly, +using a <code>tvariable</code> command. They are always 64-bit signed +integers. +</p> +<p>Trace state variables are remembered by <small>GDB</small>, and downloaded +to the target along with tracepoint information when the trace +experiment starts. There are no intrinsic limits on the number of +trace state variables, beyond memory limitations of the target. +</p> +<a name="index-convenience-variables_002c-and-trace-state-variables"></a> +<p>Although trace state variables are managed by the target, you can use +them in print commands and expressions as if they were convenience +variables; <small>GDB</small> will get the current value from the target +while the trace experiment is running. Trace state variables share +the same namespace as other “$” variables, which means that you +cannot have trace state variables with names like <code>$23</code> or +<code>$pc</code>, nor can you have a trace state variable and a convenience +variable with the same name. +</p> +<dl compact="compact"> +<dt><code>tvariable $<var>name</var> [ = <var>expression</var> ]</code></dt> +<dd><a name="index-tvariable"></a> +<p>The <code>tvariable</code> command creates a new trace state variable named +<code>$<var>name</var></code>, and optionally gives it an initial value of +<var>expression</var>. The <var>expression</var> is evaluated when this command is +entered; the result will be converted to an integer if possible, +otherwise <small>GDB</small> will report an error. A subsequent +<code>tvariable</code> command specifying the same name does not create a +variable, but instead assigns the supplied initial value to the +existing variable of that name, overwriting any previous initial +value. The default initial value is 0. +</p> +</dd> +<dt><code>info tvariables</code></dt> +<dd><a name="index-info-tvariables"></a> +<p>List all the trace state variables along with their initial values. +Their current values may also be displayed, if the trace experiment is +currently running. +</p> +</dd> +<dt><code>delete tvariable <span class="roman">[</span> $<var>name</var> … <span class="roman">]</span></code></dt> +<dd><a name="index-delete-tvariable"></a> +<p>Delete the given trace state variables, or all of them if no arguments +are specified. +</p> +</dd> +</dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Tracepoint-Actions.html#Tracepoint-Actions" accesskey="n" rel="next">Tracepoint Actions</a>, Previous: <a href="Tracepoint-Conditions.html#Tracepoint-Conditions" accesskey="p" rel="previous">Tracepoint Conditions</a>, Up: <a href="Set-Tracepoints.html#Set-Tracepoints" accesskey="u" rel="up">Set Tracepoints</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> |