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| <h3 class="section">13.3 Convenience Variables for Tracepoints</h3> |
| |
| <p><a name="index-tracepoint-variables-750"></a><a name="index-convenience-variables-for-tracepoints-751"></a> |
| |
| <a name="index-g_t_0024trace_005fframe-752"></a> |
| <dl><dt><code>(int) $trace_frame</code><dd>The current trace snapshot (a.k.a. <dfn>frame</dfn>) number, or -1 if no |
| snapshot is selected. |
| |
| <p><a name="index-g_t_0024tracepoint-753"></a><br><dt><code>(int) $tracepoint</code><dd>The tracepoint for the current trace snapshot. |
| |
| <p><a name="index-g_t_0024trace_005fline-754"></a><br><dt><code>(int) $trace_line</code><dd>The line number for the current trace snapshot. |
| |
| <p><a name="index-g_t_0024trace_005ffile-755"></a><br><dt><code>(char []) $trace_file</code><dd>The source file for the current trace snapshot. |
| |
| <p><a name="index-g_t_0024trace_005ffunc-756"></a><br><dt><code>(char []) $trace_func</code><dd>The name of the function containing <code>$tracepoint</code>. |
| </dl> |
| |
| <p>Note: <code>$trace_file</code> is not suitable for use in <code>printf</code>, |
| use <code>output</code> instead. |
| |
| <p>Here's a simple example of using these convenience variables for |
| stepping through all the trace snapshots and printing some of their |
| data. Note that these are not the same as trace state variables, |
| which are managed by the target. |
| |
| <pre class="smallexample"> (gdb) <b>tfind start</b> |
| |
| (gdb) <b>while $trace_frame != -1</b> |
| > output $trace_file |
| > printf ", line %d (tracepoint #%d)\n", $trace_line, $tracepoint |
| > tfind |
| > end |
| </pre> |
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