From owner-freebsd-arch@FreeBSD.ORG  Fri Dec 30 13:12:32 2011
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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Xin LI <delphij@gmail.com>
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Date: Fri, 30 Dec 2011 14:12:29 +0100
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	(Xin LI's message of "Thu, 29 Dec 2011 10:20:41 -0800")
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Cc: Kostik Belousov <kostikbel@gmail.com>, arch@freebsd.org, kan@freebsd.org
Subject: Re: fdlopen(3)
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Xin LI <delphij@gmail.com> writes:
> Kostik Belousov <kostikbel@gmail.com> writes:
> > Xin LI <delphij@gmail.com> writes:
> > > Will this prevent e.g. writes to the .so file after open, but
> > > before fdlopen()?
> > How can it ? Even in theory ?
> e.g. process 1 open(), check for permissions, etc., then process 2
> open() for write, write something, then process proceed with
> fdlopen()?  (We do not have mandatory "lock" on file handles to
> prevent writing I think?).

I think Kostik meant "how could you, even in theory, prevent this from
happening", and the answer is that you can't.

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