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Date:	Sat, 5 Dec 2009 10:48:55 +0100
From:	Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
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Subject:	Re: [1.7] getgroups regression?
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On Dec  4 22:48, Eric Blake wrote:
> Meanwhile, is sorting and/or pruning duplicate getgroups results something that 
> cygwin should consider doing?  POSIX is explicit that the result is a 
> mathematical set, and that two processes can have the same set membership but 
> different orders based on the sequence of events that created those two 
> processes.  But will Linux ever list a duplicate, even if duplicates appear 
> in /etc/group?

Probably not.  I assume the job of getgroups() is much easier on Linux.
It just has to list the gids in the group list.  Cygwin fetches the
/etc/group file and verifies for each entry if its SID is in the process
token.  Avoiding dups requires YA loop in the loop, I don't think it's
actually worth the effort.


Corinna

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Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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