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Re: More pipe problems (was Re: [Fwd: 1.5.11-1: sftp performance problem])

On Oct  5 12:26, Bob Byrnes wrote:
> But there is a strange twist:  When a read is pending on an empty pipe,
> then WriteQuotaAvailable is also decremented!  I can't imagine why this
> would be the case, but it is easy to demonstrate using a pair of small
> test programs that I wrote to experiment with pipe buffering.

Oh boy!

> I think my speculations about POSIX atomicity requirements related to
> PIPE_BUF were a red herring.  Ditto for hypothetical bizarre pipe
> buffering behavior.  The real problem here is NtQueryInformationFile.
> I want to first try reversing the direction of the pipe.  We don't really
> care which end is the server or client, so we could easily modify our pipe
> creation code to make an outbound pipe, and if WriteQuotaAvailable from
> NtQueryInformationFile behaves sanely, then we're done.

Yep, that sounds interesting.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader
Red Hat, Inc.

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