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Subject: RE: fifos and named pipes
Date: Wed, 28 Mar 2001 10:33:29 +1000
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From: "Robert Collins" <robert DOT collins AT itdomain DOT com DOT au>
To: <cygwin-developers AT cygwin DOT com>
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> -----Original Message-----
> From: Christopher Faylor [mailto:cgf AT redhat DOT com]
> Sent: Wednesday, March 28, 2001 10:20 AM
> To: cygwin-developers AT cygwin DOT com
> Subject: Re: fifos and named pipes
> 
> 
> On Wed, Mar 28, 2001 at 09:06:14AM +1000, Robert Collins wrote:
> >Just thought you'd like to know: named pipes under win32 (which I was
> >considering using for the NT implementations) don't have the same
> >semantics as under openBSD.... so I'm going with my roll-your-own
> >approach .
> 
> What about regular pipes?  I suggested that you could just use those
> along with some glue to duplicate handles between processes.

I haven't tested anonymous pipes yet. Even if I do use those, I need the
glue to identify what pipes are available first - that's what I'm on now
(step 3 of 5). I plan to look at that once I've got a rough-and-ready
implementation going. 
 
> How do the semantics differ?

In win32, each "server" opens one or more instances of a given named
pipe. Only one "client" can attach to one instance. The handles can be
duplicated as much as needed. So we could pass the client handles
around, to get the single writer, many readers working. However I don't
think we can do that with the "server" handle. 
 
> cgf
> 

Rob