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From: "David Schwartz" <davids@webmaster.com>
To: =?iso-8859-1?Q?=C9ric_Brunet?= <ebrunet@quatramaran.ens.fr>,
        <linux-kernel@vger.kernel.org>
Subject: RE: Children first in fork
Date: Thu, 19 Apr 2001 05:07:11 -0700
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> Hello all,
>
> I have read on lwn.net that the patch that makes children run first after
> a fork has been integrated in the latest pre-kernel.
>
> I am a little bit concerned by that, as I have begun to write a program
> that monitors process using ptrace. The difficulty is to ptrace-attach
> the child in a fork before it can do anything unmonitored. When the
> parent runs first, the return from the fork system called is trapped by
> the monitor program which has enough time to ptrace-attach the child. If
> the child runs first, it is not even remotely the case anymore.
>
> I understand that performance is more important that the possibility to
> ptrace across forks, but I still think that there should be a way to
> attach the children of a ptraced-process. Is there currently a way to
> achieve this in the kernel that I am not aware of ?

	It seems to me that what you really want is a fork option to create the
child in a suspended state.

	DS

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