external systemtap meeting notes 20070816

[Roland McGrath]

> Would this hack work: have the second utrace engine refuse to put a
> breakpoint wherever it suspects another engine may have put one?  

Sure, it's easy to notice the breakpoint instruction already there.

> Or even more pessimistically, can an engine know that another one is
> already monitoring a given target process, and give up at attach time?
> (That would defeat some of the promise of utrace, but so it goes.)

Yes, it can (UTRACE_ATTACH_EXCLUSIVE).


Thanks,
Roland