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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Mel Flynn <mel.flynn+fbsd.hackers@mailing.thruhere.net>
References: <200910090015.24175.mel.flynn+fbsd.hackers@mailing.thruhere.net>
Date: Fri, 09 Oct 2009 11:38:29 +0200
In-Reply-To: <200910090015.24175.mel.flynn+fbsd.hackers@mailing.thruhere.net>
	(Mel Flynn's message of "Fri, 9 Oct 2009 00:15:24 +0200")
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Running a program through gdb without "interfering"
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Mel Flynn <mel.flynn+fbsd.hackers@mailing.thruhere.net> writes:
> is there a way to have a program run through gdb and gdb only record a=20
> segfault, but otherwise let the program run?

Yes, just run "gdb /path/to/program" and type "run".

> [...] sudo *sometimes* segfaults [...] However, it doesn't dump core

sudo(1) is setuid root.  You need to set kern.sugid_coredump to get it
to dump core.

> [1] In order to get this working I had to put a statically compiled ps in=
 the=20
> jail, or the uid test would fail. It has the downside that it lists both =
jail=20
> and host processes, [...]

Uh, no.  Processes outside the jail are not visible inside it, no matter
what version of ps(1) or top(1) or any other such program you use.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no