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Message-ID: <3EF29BD7.1010708@ece.gatech.edu>
Date: Fri, 20 Jun 2003 01:29:59 -0400
From: Charles Wilson <cwilson AT ece DOT gatech DOT edu>
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To: cygwin AT cygwin DOT com
Subject: Re: [PATCH] make cygipc semaphores persistent
References: <3EF205FA DOT 5030504 AT hekimian DOT com>
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Joe Buehler wrote:

> The semaphores provided by the 1.14-1 version of cygipc are not 
> persistent -- once
> all client processes close a semaphore, it disappears.  This is 
> different than standard
> UNIX semantics, in which semaphores persist until removed or system 
> reboot.  The
> attached patch fixes this, providing the standard UNIX semantics for 
> semaphore lifetime.
> (Semaphores will persist until ipc-daemon is killed).
> 
> I would appreciate it if the owner(s) of cygipc review this patch and 
> roll it in
> to the "official" distribution if it looks OK.  The basic trick is that 
> the ipc-daemon
> process needs to keep an open handle for all semaphores in a non-removed 
> state.
> It looks as though there was code in cygipc that attempted this, but it 
> was removed in
> version 1.04.
> 
> I have included a couple typo fixes in the patch also.


This patch looks right to me, given the intent.  However, I'll have to 
take your word for standard 'persistence' behavior...

I'll incorporate this patch -- but I don't want to mess with cygipc-1.15 
right now.  Let's save this for cygipc-2.x, which should come out Real 
Soon after cygwin-1.5.0.  Which itself is due RSN.

--Chuck



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