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Date: Thu, 15 Jan 2009 21:17:13 +0100
From: Ruediger Pluem <rpluem@apache.org>
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To: dev@httpd.apache.org
Subject: Re: mod_backtrace and mod_whatkilledus to trunk?
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On 01/15/2009 07:39 PM, Jeff Trawick wrote:
> On Thu, Jan 15, 2009 at 12:40 PM, "Pl�m, R�diger, VF-Group" <
> ruediger.pluem@vodafone.com> wrote:

>>
>> Another option would be to add this hook by default and prevent its
>> execution by a directive (haven't dug into this to check if this is
>> possible).
> 
> 
> which reminds me: The 2.x hook is already protected both by a configure
> option which defaults to no and a directive which defaults to Off ;)
> 
> See http://httpd.apache.org/docs/2.2/mod/mpm_common.html#enableexceptionhook
> 
> See some comments from Joe about why not to even allow the directive by
> default at https://bugzilla.redhat.com/show_bug.cgi?id=205627

Thanks for the pointer. I agree with Joe that it is better to analyse the
core dump afterwards, but I don't see that setting AP_ENABLE_EXCEPTION_HOOK
and setting EnableExceptionHook to Off really hurts us in this respect.
We already catch "core dump signals" to change the current working dir to
dump the core in the correct place. If EnableExceptionHook is set to Off
we just call one additional static function (run_fatal_exception_hook) and
check a static variable in an if statement. We could even integrate the code
of run_fatal_exception_hook into sig_coredump without any pain.
So from my current point of view I tend to say:

enable enableexceptionhook by default and let EnableExceptionHook default
to off (as currently).

But Joe has always very good arguments, so he may make me change my mind again :-).

Regards

R�diger