From owner-freebsd-hackers  Wed Apr  3 17:40:35 2002
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Date: Wed, 3 Apr 2002 17:29:44 -0800 (PST)
From: Julian Elischer <julian@elischer.org>
To: Ramkumar Chinchani <rc27@cse.Buffalo.EDU>
Cc: "Tim J. Robbins" <tim@robbins.dropbear.id.au>,
	freebsd-hackers@FreeBSD.ORG
Subject: Re: Ptracing each other
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if you consider that each process can only do damage with system calls,
what you REALLY want is to use ktrace (or the truss equivalent syscalls)
but why do you want the untrusted client to watch the watcher?
it seems that you must end up in an infinite loop because it will see it
doing the watching which will generate action which the other will
see ....


On Wed, 3 Apr 2002, Ramkumar Chinchani wrote:

> 
> The requirement is that I have a theoretical framework where no process
> trusts the other. So they watch (trace) each process.
> 
> -Ram
> 
> ==> Julian Elischer <julian@elischer.org>/5:09pm/Apr 3, 2002 <==
> 
> [but I'm confused..
> [to trace a program you need to be gdb
> [(or similar)  why would one gdb gdb when it's gdbing you?
> [Maybe you need to explain WHY rather than WHAT.
> [
> [
> [On Wed, 3 Apr 2002, Ramkumar Chinchani wrote:
> [
> [>
> [> Track means to basically trace the execution and watch the events that
> [> occur without any interprocess communication.
> [>
> [> -Ram
> [>
> [> ==> Julian Elischer <julian@elischer.org>/4:59pm/Apr 3, 2002 <==
> [>
> [> [that depends on what you mean by "track"
> [> [
> [> [
> [> [On Wed, 3 Apr 2002, Ramkumar Chinchani wrote:
> [> [
> [> [>
> [> [> Can two processes track each other through the proc file system then?
> [> [>
> [> [> I want a scenario where process P1 and P2 track each others execution.
> [> [>
> [> [> Is this possible at all?
> [> [>
> [> [> Thanks.
> [> [>
> [> [> -Ram
> [> [
> [>
> [>
> [
> 
> 


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