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Date: Tue, 18 May 2010 00:40:54 -0700
From: Alfred Perlstein <alfred@freebsd.org>
To: Dan McNulty <dkmcnulty@gmail.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Efficient way to determine when a child process forks or calls
	exec
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* Dan McNulty <dkmcnulty@gmail.com> [100517 08:02] wrote:
> Hi all,
> 
> I have been experimenting with ptrace to determine when a child
> process forks or calls exec. Particularly, I have explored tracing
> every system call entry and exit similar to what the truss utility
> does, and for my case, the performance impact of tracing every system
> call is too great.
> 
> Is there a more efficient way than tracing every system call entry and
> exit to determine when a child process forks, calls exec, or creates a
> new LWP?
> 
> Thanks a lot for your help!

kevent has some hooks, have you looked at that?

-- 
- Alfred Perlstein
.- AMA, VMOA #5191, 03 vmax, 92 gs500, 85 ch250, 07 zx10
.- FreeBSD committer