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Date: Wed, 04 Nov 2009 12:25:11 -0600
From: Alan Cox <alc@cs.rice.edu>
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Cc: alc@freebsd.org, freebsd-hackers@freebsd.org,
	Alexander Best <alexbestms@math.uni-muenster.de>
Subject: Re: mmap(2) with MAP_ANON honouring offset although it shouldn't
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Ed Schouten wrote:
> * John Baldwin <jhb@freebsd.org> wrote:
>   
>> Note that the spec doesn't cover MAP_ANON at all FWIW.
>>     
>
> Yes. I've noticed Linux also uses MAP_ANONYMOUS instead of MAP_ANON.
> They do provide MAP_ANON for compatibility, if I remember correctly.
>
>   

For what it's worth, I believe that Solaris does the exact opposite.  
They provide MAP_ANONYMOUS for compatibility.  It seems like a good idea 
for us to do the same.

We also have an unimplemented option MAP_RENAME defined for 
compatibility with "Sun" that is nowhere mentioned in modern Solaris 
documentation.

Alan