bug#6758: 23.2; xterm.el: please provide an option to not discard input in terminal-init-xterm

[Stefan Monnier <monnier@iro.umontreal.ca>]

> I can also imagine a more complete fix that would involve not flushing
> the input buffer, and interpreting the Xterm responses in a more
> asynchronous fashion:
> - Don't discard input
> - Send the \e[>0c probe
> - Allow input into the buffer as usual, but for the next few seconds,
>   interpret \e[>0;251;0c responses and perform
>   (xterm-turn-on-modify-other-keys) etc. as necessary.

Time-dependent processing is considered brittle (especially when
working remotely via something like SSH), so we prefer to avoid it.
Especially since coding it right could prove pretty darn tricky.

OTOH, I thought we had agreed that we need to add a configuration
variable xterm-turn-on-modify-other-keys which could be set to t or nil
to force the modifyOtherKeys feature of Xterm ON or OFF without first
checking whether the current xterm indeed supports it or not.
Its default value would be `auto', which would first check for support
and then turn it ON if applicable.
Since the "discard input" is needed for the check, this would solve
your problem.

Now, I don't see such a variable, so either I misremeber, or the patch
was never written, or never committed, ...


        Stefan