tags/lttv-0.10.0-pre15-12082008/doc/developer/developer_guide/html/x46.html

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  77 >2.2. Why an event driven trace reader ?</A
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  80 >&#13;The complexity of synchronizing the tracesets is then hidden to the viewer. Some
  81 future plans involve to be able to put many traces together in a trace set.
  82 Before this becomes possible, the time of each trace must be synchronized in
  83 some way. Some work is actually done to create a module that uses the network
  84 traffic shared by different computers to synchronize the time of different
  85 traces.
  86 </P
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  88 >&#13;In order to make each module integrate well with each other, we made the trace
  89 reader a simple hook caller. For each event it reads, it just calls the hook
  90 lists for this event. For each event, it calls the by_id specific hooks
  91 registered for this event and also the "main" hooks, registered for all events.
  92 Note that the two hook lists are merged when called so the priority of the
  93 hooks of each list is respected. For example, a hook of higher priority (20) in
  94 the main list will be called before a hook of lower priority (40) from the
  95 by_id specific list.
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