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From: ebiederm@xmission.com (Eric W. Biederman)
To: Bill Davidsen <davidsen@tmr.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>, Ingo Molnar <mingo@elte.hu>,
       Robin Holt <holt@sgi.com>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Chris Snook <csnook@redhat.com>, linux-kernel@vger.kernel.org,
       Jack Steiner <steiner@americas.sgi.com>
Subject: Re: init's children list is long and slows reaping children.
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Date: Wed, 11 Apr 2007 14:17:13 -0600
In-Reply-To: <461D3D3E.2060709@tmr.com> (Bill Davidsen's message of "Wed, 11
	Apr 2007 15:55:42 -0400")
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Bill Davidsen <davidsen@tmr.com> writes:

> As long as the original parent is preserved for getppid(). There are programs
> out there which communicate between the parent and child with signals, and if
> the original parent dies, it undesirable to have the child getppid() and start
> sending signals to a program not expecting them. Invites undefined behavior.

Then the programs are broken.  getppid is defined to change if the process
is reparented to init.

Eric