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Message-ID: <3753E298.16B46F37@vinschen.de>
Date: Tue, 01 Jun 1999 15:39:36 +0200
From: Corinna Vinschen <corinna AT vinschen DOT de>
MIME-Version: 1.0
To: Chris Faylor <cgf AT cygnus DOT com>, cygwin-developers AT sourceware DOT cygnus DOT com
Subject: [Fwd: shm]
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I forward this, because I noticed this problem only when I read
Suhaib's mail. IMHO, the `mmap' problem should be solved, too,
before releasing B21. As minimal change, the call to `CreateFileMapping'
should get a `sec_all' security descriptor instead of `sec_none'.

Corinna Vinschen wrote:
> 
> Horak Daniel wrote:
> >
> > > Has anyone a SVR4 style shared memmory for Cygwin
> > > (shmget/shmctl/shmat)?  I need it for X-server
> > > for Cygwin Development.
> > >
> > > The ipc available for Cygwin from France (do not remember the URL) has
> > > problems.  Its headers gives the problems.
> >
> > I am using the cygipc library v1.03
> > (http://www.multione.capgemini.fr/tools/pack_ipc/) succesfully in the port
> > of PostgreSQL database system. It required only to comment CURRENT_TIME in
> > some header.
> >
> >                         Dan
> 
> Caution!
> 
> The security settings of this package are not sufficent for multi user
> systems! The security descriptor, that is given to `CreateSemaphore'
> is a default descriptor. The result is, that only the creator/owner
> of the semaphore may use it.
> 
> Moreover, the cygwin call `mmap' which is used in the package, is not
> implemented with sufficent correspondence between the given permissions
> and the resulting security descriptor in the windows call
> `CreateFileMapping'. It uses the default descriptor, too :(
> 
> Regards,
> Corinna

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