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From: Mike Buland <xagafinelle@gmail.com>
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Subject: Re: What is the process group hack
Date: Thu, 26 Apr 2012 09:52:12 -0600
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Hello,

At least one good example is getty processes.  There are a number of
systems (including newer linux kernels, but this may be optional) that
will not allow a process that is not the parent of it's own process
group to take an unclaimed terminal device as it's controlling
terminal.  getty programs don't generally make their own process
groups, and neither does runit for it's services, so the program group
hack is necessary to run a getty program on many systems.

Although I believe that you're right, it was intended in daemontools
as a way to try to supervise a process that wanted to daemonize, I've
never had experience using it in that capacity myself.

--Mike Buland

On Thu, Apr 26, 2012 at 9:15 AM, harish badrinath
<harishbadrinath@gmail.com> wrote:
> Hello,
>
> I Could not figure out what "process group hack" is supposed to be
> utilized for ??
> Is it used to supervise daemons that stubbornly fork into the background.
> Could anyone please explain with an example, i would be really helpful.
> I have to the best of my abilities RTFM'ed and searched the internet.
>
> Thank you,
> Harish