ktrace -c behavior

John-Mark Gurney jmg at funkthat.com
Fri Aug 22 19:20:36 UTC 2014

Eric van Gyzen wrote this message on Fri, Aug 22, 2014 at 15:16 -0400:
> What behavior would you expect from this sequence of commands?
>     ktrace -tw -p 1234
>     ktrace -c -p 1234
> Based on this...
>      -c      Clear the trace points associated with the specified file
> or processes.

and/or just add specified:
Clear the specified trace points ...

> ...I would expect the second command to clear the trace point for
> context switches.  It doesn't.  I have to specify -tw with the -c to get
> that behavior.  This makes sense; it's just not what I was expecting.
> Assuming we want to keep this behavior, can we clarify the -c flag in
> man page?  I would suggest:
>     If the -t flag is not specified, clear the default set of trace points.

Maybe we should add a new trace point string that is a (for all).. so
you can do ktrace -ta -c?

  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."

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