Bug#273194: xterm: characters from paste buffer lost at roughly 4kB intervals [kernel pty bug?]

[Vincent Lefevre <vincent@vinc17.net>]

On 2023-01-23 03:11:59 +0100, Vincent Lefevre wrote:
> On 2006-10-14 15:56:10 -0400, Thomas Dickey wrote:
> > On Sat, Oct 14, 2006 at 08:20:14PM +0200, Andrew Moise wrote:
> > >  I still see this misbehavior with xterm 210-3.1 and
> > > linux-image-2.6.17-2-686 2.6.17-9.
> > 
> > I can see it (now) with a 2.6.15 kernel (814 lines copied).
> > I also note that Branden got no followup from the kernel people.
> 
> This also occurs with
> 
> Linux zira 6.1.0-2-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.7-1 (2023-01-18) x86_64 GNU/Linux
> 
> and xterm, mlterm and GNOME Terminal at least. This would confirm
> a kernel pty bug (unless this is a documented pty limitation, in
> which case the applications would have to take it into account...
> but they could try to implement a workaround in any case).
> 
> For me, with the above kernel, the limit is 4095 bytes.
> 
> An annoying consequence is that Ctrl-C no longer works, which can
> yield buggy commands executed by the shell after an accidental
> paste while a foreground X command is running (presumably because
> bracketed paste is not in effect, so that each newline character
> validates each line as a command). See
>   https://lists.debian.org/debian-user/2023/01/msg00520.html

Actually, in my case (where I do a large paste after starting a
command that doesn't consume input, typically an X command), this is
a different, but related issue. The characters are not really lost,
but delayed. Still, the behavior is incorrect: the characters,
including Ctrl-C, are kept in some xterm buffer, so that the Ctrl-C
doesn't have an immediate effect: it takes effect only near the end
of the paste (after the command has ended), and this is too late.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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