Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com X-Originating-IP: [66.206.205.2] X-Originating-Email: [vxj45 AT hotmail DOT com] From: "Vishal Jain" To: cygwin AT cygwin DOT com Subject: Re: /etc/passwd dependency of cygwin Date: Fri, 21 Mar 2003 19:19:29 -0800 Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 22 Mar 2003 03:19:29.0298 (UTC) FILETIME=[D9792F20:01C2F021] fopen doesn't work if I have my own implementation of seteuid. fopen call which goes to fhandler.cc:open-> security.cc:set_security_attribute-> security.cc:alloc_sd relies on uid to sid mapping in /etc/passwd or on the current uid set in the heap(which would be incorrect in my case as I have my own implementation of seteuid). If there is a way to disable nt security in cygwin on win2k then this might work as security descriptor won't be created in that case. Vishal 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!" ;-) _________________________________________________________________ Protect your PC - get McAfee.com VirusScan Online http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963 -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/