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X-Authentication-Warning: slinky.cs.nyu.edu: pechtcha owned process doing -bs
Date: Tue, 18 Mar 2003 20:51:15 -0500 (EST)
From: Igor Pechtchanski <pechtcha AT cs DOT nyu DOT edu>
Reply-To: cygwin AT cygwin DOT com
To: Vishal Jain <vxj45 AT hotmail DOT com>
cc: cygwin AT cygwin DOT com
Subject: Re: /etc/passwd dependency of cygwin
In-Reply-To: <F136ING71G0aINdXKFV00039b00@hotmail.com>
Message-ID: <Pine.GSO.4.44.0303182045530.561-100000@slinky.cs.nyu.edu>
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On Tue, 18 Mar 2003, Vishal Jain wrote:

> Hi,
> How does cygwin library depend on uid's and gid's in /etc/passwd?
> If I replace it with my custom /etc/passwd file and replace cygwin's
> seteuid/geteuid calls with custom implementation, will my application work?
> How does cygwin internally uses uid's and gid's?
> thanks,
> Vishal

Vishal,

AFAIU, there has to be some way of mapping Windows SIDs to Cygwin's
[ug]ids (on NT systems), and the [ug]ids have to be unique, but I don't
think they are constrained much otherwise.  You might find out more by
searching the Cygwin documentation, especially the User's Guide and the
API reference, for "ntsec".

If you plan to make a fundamental change like that to your Cygwin DLL, you
might want to read the recent discussions regarding ntsec on the
cygwin-developers list carefully.  There are some tricky issues, IIRC.

And, as always, the code itself is the best (or, at least, the most
up-to-date) documentation...  "Use the source, Luke!" ;-)
	Igor
-- 
				http://cs.nyu.edu/~pechtcha/
      |\      _,,,---,,_		pechtcha AT cs DOT nyu DOT edu
ZZZzz /,`.-'`'    -.  ;-;;,_		igor AT watson DOT ibm DOT com
     |,4-  ) )-,_. ,\ (  `'-'		Igor Pechtchanski
    '---''(_/--'  `-'\_) fL	a.k.a JaguaR-R-R-r-r-r-.-.-.  Meow!

Oh, boy, virtual memory! Now I'm gonna make myself a really *big* RAMdisk!
  -- /usr/games/fortune


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