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To: "Henry S. Thompson" <ht AT inf DOT ed DOT ac DOT uk>, cygwin AT cygwin DOT com
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From: Andrey Repin via Cygwin <cygwin AT cygwin DOT com>
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Greetings, Henry S. Thompson!

>> ...

>> The main change was that we stopped using Win32 Overlapped I/O
>> (https://docs.microsoft.com/en-us/windows/win32/sync/synchronization-and-overlapped-input-and-output)
>> and switched to using the NT API.  As a result, pipe I/O became much
>> more efficient.  It wouldn't surprise me if the efficiency alone is
>> what exposed the bug.
>>
>> The good news is that the bug doesn't seem to occur in XEmacs 21.4
>> (on 32-bit Cygwin).  So one way to approach this would be to bisect
>> the XEmacs git repo to find the commit that introduced the bug.
>> You'd probably have to do the work on 32-bit Cygwin since, if I
>> remember correctly, XEmacs 21.4 didn't build on 64-bit Cygwin.

> Right, although I _suspect_ it will be in 64-bit-only code.  Easy
> enough to find out, once I resurrect a 32-bit install on a spare
> machine that I can run 3.3 on (I use XEmacs all day every day from my
> day job, so I need to stay with 3.2 until we fix this).

> So, this may take a while, unless someone else hits the problem and
> finds a simpler test case.

You can install as many Cygwin setups as you need on the same machine.
They are not stepping on each other toes.
Though I strongly require a virtual machine for such exercises.


-- 
With best regards,
Andrey Repin
Thursday, November 11, 2021 2:06:01

Sorry for my terrible english...


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