problem with readonly pinfo?

Christopher Faylor cgf@redhat.com
Wed Sep 17 20:05:00 GMT 2003


On Wed, Sep 17, 2003 at 10:03:37PM +0200, Corinna Vinschen wrote:
>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.

It sure would.  I always wondered if there was a backdoor way to create
a named pipe on the Windows 9x family but google says no...

cgf



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