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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Alfred Perlstein <alfred@freebsd.org>
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Date: Fri, 29 May 2009 11:49:21 +0200
In-Reply-To: <20090528213017.GX67847@elvis.mu.org> (Alfred Perlstein's message
	of "Thu, 28 May 2009 14:30:17 -0700")
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Cc: Nate Eldredge <neldredge@math.ucsd.edu>, yuri@rawbw.com,
	freebsd-hackers@freebsd.org
Subject: Re: Why kernel kills processes that run out of memory instead of
	just failing memory allocation system calls?
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Alfred Perlstein <alfred@freebsd.org> writes:
> Dag-Erling Sm=C3=B8rgrav <des@des.no> writes:
> > Usually, what you see is closer to this:
> >=20
> > if ((pid =3D fork()) =3D=3D 0) {
> >         for (int fd =3D 3; fd < getdtablesize(); ++fd)
> >                 (void)close(fd);
> >         execve(path, argv, envp);
> >         _exit(1);
> > }
>
> I'm probably missing something, but couldn't you iterate=20
> in the parent setting the close-on-exec flag then vfork?

This is an example, Alfred.  Like most examples, it is greatly
simplified.  I invite you to peruse the source to find real-world
instances of non-trivial fork() / execve() usage.

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