setup will have to wait :[

Robert Collins
Sun Mar 25 13:59:00 GMT 2001

----- Original Message -----
From: "Christopher Faylor" <>
To: "Egor Duda" <>
Sent: Monday, March 26, 2001 7:53 AM
Subject: Re: setup will have to wait :[

> On Mon, Mar 26, 2001 at 07:46:35AM +1000, Robert Collins wrote:
> >----- Original Message -----
> >From: "Egor Duda" <>
> >Subject: Re: setup will have to wait :[
> >
> >
> >> Hi!
> >>
> >> Saturday, 24 March, 2001 Robert Collins
> >wrote:
> >>
> >Right, so _how do we pass the fd_ to the child process? I'll look
> >spawn and fork. Worst case though: fifos are cygwin only. Best case I
> >find some way of tricking the OS into loading up the cygwin code and
> >writing "through it". Hmm I wonder if an IFS could do this (How much
> >work did I think this was going to be ?!).
> They're inherited automatically.  The fd table is copied
> Non-cygwin processes inherit the handles but they won't know what to
> with them since they don't understand cygwin fds.


> >> RC> I know that cygwin already has named pipe support
> >>
> >> ? what do you mean by this? do you mean native calls such as
> >> CreateNamedPipe () etc. or something else?
> >
> >>From comments about sshd and cvs on 9x and the syncronisation
problems -
> >so I may be off base. I haven't checked the code. Implementing this
> >Named Pipes will be just as tricky as far as non-cygwin programs
> >won't it?.
> You can't use named pipes.  You can't create them on Windows 95.

Well I'm glad I wasn't planning on useing them anyway :]

> Cygwin doesn't implement named pipes.  Isn't a fifo == a named pipe
> anyway?

Yes. I'm looking into the behaviour in more detail defore I cut code,
but yes. My planned implementation is a shared memory region that lists
the named pipes open on the system (maintained automagically via any
open cygwin process), a couple of waitable objects (probably 1 semaphore
and 1 event) per open fifo, and finally a (pick a good buffer size)
shared memory region for doing the actual data transfer.

> cgf


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