Message-ID: <32576391.post@talk.nabble.com>
Date: Sat, 1 Oct 2011 19:36:49 -0700 (PDT)
From: gsingh93 <gsingh_2011 AT yahoo DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: Different commands give different groups
In-Reply-To: <4E871BAF.3040106@redhat.com>
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That makes sense, but I've completely restarted my computer and yet it still
shows the old groups. So a new process that uses the new groups hasn't
started. Any idea why?

eblake wrote:
> 
> On 09/30/2011 09:49 PM, gsingh93 wrote:
>>
>> Why do these two commands give different groups? It's the same user.
> 
> Because the effective gid set for the existing process differs from the 
> recorded groups in /etc/groups - most likely, you've changed /etc/groups 
> but haven't logged out and back in to start a new process hierarchy that 
> uses the new groups.
> 
>>
>> Gulshan AT GSJK-PC /etc
>> $ id Gulshan
>> uid=1000(Gulshan) gid=545(Users) groups=545(Users),0(root)
> 
> That's what the groups will be if a new process is started for Gulshan.
> 
>>
>> Gulshan AT GSJK-PC /etc
>> $ id
>> uid=1000(Gulshan) gid=545(Users) groups=545(Users),513(None)
> 
> Whereas that's what the groups are now for the current process.
> 
> This aspect of your situation is not cygwin-specific, the same behavior 
> can be observed in other OSs when you change the user database after a 
> particular user already has a process started.
> 
>>
>> Furthermore, the commands mkgroup and mkpasswd give the orginial states
>> of
>> their corresponding files instead of what I changed them to. Why is that?
> 
> This part is cygwin-specific - and the answer is that mkgroup and 
> mkpasswd are querying Window's database of user information, not /etc 
> (so that you can then populate /etc with information that matches the 
> Window's database).  Windows doesn't care what you put in /etc, so the 
> amount of changes you can make in those files that still have a 
> worthwhile visible effect to cygwin processes is a bit limited.
> 
> -- 
> Eric Blake   eblake AT redhat DOT com    +1-801-349-2682
> Libvirt virtualization library http://libvirt.org
> 
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