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Date: Sat, 22 Sep 2012 16:46:06 -0700
From: Linda Walsh <cygwin AT tlinx DOT org>
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Subject: Re: Win PTY library.
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Václav Zeman wrote:
> I think that the difference is that PTY is a stream of commands that get
> interpreted, OTOH, polled Windows console can provide only a snapshot at
> some point in time. It seems that it would be hard to produce faithful
> stream of commands from this console snapshot. Because Console2 is only
> visualizing the snapshot in its own GUI window, it does not matter that it
> is doing that by snapshotting the hidden console. But for the PTY
> abstraction, a faithful chain of commands seems necessary. I think that any
> such polling based implementation could miss some transitions in the PTY
> state in between the polls.
----
	I'd have to agree with Václav.

If you are using the pty interactively, it won't be problem, BUT
programs use pty's to drive other programs, programatically, and
rely on "pipe" type speeds to be able to communicate to them.

Imagine rsync, which goes over pipes -- if it sprayed through data
at full speeds, that only got picked up every 100ms -- i'd imagine
alot more than a screen full of data would go by in the transfer.

I am working on a program right now that starts a inspection tool
then issues commands to it -- I want to be able to query about
100-200K files... if those take even a full ms. each, I'm
looking at over 3 minutes.  If polling resulted in me getting
back results every 10ms, it'd be over a half an hour...way
not good.

Won't even think about 100ms / result..... tried... now my head hurts.

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