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Date: Mon, 1 Jun 2020 19:47:32 +0900
To: cygwin AT cygwin DOT com
Subject: Re: Repeated input in PTY with SSH when a native process runs a
 Cygwin process that consumes input
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From: Takashi Yano via Cygwin <cygwin AT cygwin DOT com>
Reply-To: Takashi Yano <takashi DOT yano AT nifty DOT ne DOT jp>
Cc: Andrew Ng <anng DOT sw AT gmail DOT com>
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On Sun, 31 May 2020 13:00:51 +0100
Andrew Ng <anng DOT sw AT gmail DOT com> wrote:
> > The developers snapshot, in which the issue has been fixed,
> > is ready. Could you please test?
> 
> Thanks for the fast response.
> 
> I have tested the snapshot and can confirm that it fixes the issue. I
> have also applied the same fix to MSYS2 and confirmed the issue is
> fixed there too.

Thanks for testing.

> I did take a look at the code when I came across this issue and I
> noticed a few things that looked a bit odd. I noticed that the
> following functions appear to make use of rabuf () without
> consideration for raixget ():
> 
>   fhandler_termios::eat_readahead
>   fhandler_pty_master::accept_input
>   fhandler_pty_master::transfer_input_to_pcon
> 
> Also fhandler_pty_slave::eat_readahead does 'eols' processing without
> any guard on is_line_input (), which seems to differ from the code
> pattern seen elsewhere.
> 
> I don't know if these are important, but thought I should mention
> them, just in case.

Thank you for your advice. I will check if these can cause any
problem.

As for pty master, get_readahead() is not used at all, so raixget()
is always 0. So pty master code does not cause problem.

However, it is certainly dangerous. I will consider how these
should be.

-- 
Takashi Yano <takashi DOT yano AT nifty DOT ne DOT jp>
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