From owner-freebsd-hackers  Fri Jun 28 11:17:49 1996
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Date: Fri, 28 Jun 1996 01:49:59 GMT
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From: James Raynard <fhackers@jraynard.demon.co.uk>
To: alk@think.com
CC: jkh@time.cdrom.com, hackers@freebsd.org
In-reply-to: <199606272030.PAA26920@compound.Think.COM> (message from Tony
	Kimball on Thu, 27 Jun 1996 15:30:57 -0500 (CDT))
Subject: Re: longstanding, woeful inadeqacy
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> : > Easier in what sense?  It is essentially impossible to debug anything
> : > that forks, since by the time you can attach to it, it has gone
> : > veering wildly out of control.
> : 
> : Not if you put a sleep loop in it
> 
> And if I don't have source code?  Or a compiler?
> Or if the insertion of the sleep loop fixes the compiler bug
> which I was trying to find in the first place?

UT(K)SL and move the sleep loop into the exec() system call?

> Or if the sleep loop prevents the process from meeting a
> synchronization constraint which makes it impossible to
> debug the original execution profile?

Hmm. Maybe you could replace the exec()'d program with a wrapper that
ktrace's it...

Seriously though, it would be nice to get something like strace
working for these cases, but /proc doesn't support features like
system call tracing.

-- 
James Raynard, Edinburgh, Scotland
james@jraynard.demon.co.uk