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Re: problem with readonly pinfo?
On Wed, Sep 17, 2003 at 03:41:34PM -0400, Christopher Faylor wrote:
> On Wed, Sep 17, 2003 at 08:23:42PM +0200, Corinna Vinschen wrote:
> >Weird enough, they implemented overlapped IO for named pipes. Just for
> >anonymous pipes (and therefore not on 9x/Me) it's not implemented.
>
> Yeah. Have you ever tested overlapped I/O on regular pipes on NT? I think
> I have but I don't remember the results. I've suspected that anonymous pipes
> are just named pipes under the hood.
Anonymous pipes are actually named pipes under NT. That's documented
in MSDN. Unfortunately, using overlapped IO requires to call
CreateNamedPipe(name, FILE_FLAG_OVERLAPPED, ...) so the OS must know
about overlapped IO on pipe creation. That disqualifies anonymous pipes
for overlapped operation. Too bad. Named pipes can be bidirectional.
I guess it would simplify Cygwin enormously, if we could use named pipes
for pseudo ttys, signals(?), etc.
Corinna
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