mingw/info/gdb/Analyze-Collected-Data.html

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  12 Node:<a name="Analyze%20Collected%20Data">Analyze Collected Data</a>,
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  19 <h3 class="section">Using the collected data</h3>
  20
  21    <p>After the tracepoint experiment ends, you use GDB commands
  22 for examining the trace data.  The basic idea is that each tracepoint
  23 collects a trace <dfn>snapshot</dfn> every time it is hit and another
  24 snapshot every time it single-steps.  All these snapshots are
  25 consecutively numbered from zero and go into a buffer, and you can
  26 examine them later.  The way you examine them is to <dfn>focus</dfn> on a
  27 specific trace snapshot.  When the remote stub is focused on a trace
  28 snapshot, it will respond to all GDB requests for memory and
  29 registers by reading from the buffer which belongs to that snapshot,
  30 rather than from <em>real</em> memory or registers of the program being
  31 debugged.  This means that <strong>all</strong> GDB commands
  32 (<code>print</code>, <code>info registers</code>, <code>backtrace</code>, etc.) will
  33 behave as if we were currently debugging the program state as it was
  34 when the tracepoint occurred.  Any requests for data that are not in
  35 the buffer will fail.
  36
  37 <ul class="menu">
  38 <li><a accesskey="1" href="tfind.html#tfind">tfind</a>:                        How to select a trace snapshot
  39 <li><a accesskey="2" href="tdump.html#tdump">tdump</a>:                        How to display all data for a snapshot
  40 <li><a accesskey="3" href="save-tracepoints.html#save-tracepoints">save-tracepoints</a>:             How to save tracepoints for a future run
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