On the impossibility to use escape sequences when the networks hangs

[Steffen Nurpmeso]

Theo de Raadt wrote in
 <6240.1760455482 at cvs.openbsd.org>:
 |Steffen Nurpmeso <steffen at sdaoden.eu> wrote:
 |> Damien Miller wrote in
 |>  <89d93aab-0510-31a4-9542-45a718702591 at mindrot.org>:
 |>|On Mon, 13 Oct 2025, Dennis Clarke via openssh-unix-dev wrote:
 |>|
 |>|> Seems to work fine at the beginning of a line. :/
 |>|
 |>|This was improved relatively recently:
 |>|
 |>|commit fec014785de198b9a325d1b94e324bb958c5fe7b
 |>|Author: djm at openbsd.org <djm at openbsd.org>
 |>|Date:   Wed Apr 20 04:19:11 2022 +0000
 |>|
 |>|    upstream: Try to continue running local I/O for channels in state
 |>|    
 |>|    OPEN during SSH transport rekeying. The most visible benefit \
 |>|    is that it
 |>|    should make ~-escapes work in the client (e.g. to exit) if the \
 |>|    connection
 |>|    happened to have stalled during a rekey event. Based work by and \
 |>|    ok dtucker@
 |>|    
 |>|    OpenBSD-Commit-ID: a66e8f254e92edd4ce09c9f750883ec8f1ea5f45
 |>|
 |>|Before this change (in OpenSSH 9.1), an unresponsive connection might
 |>|get uninterruptibly stuck if it was in the process of rekeying but
 |>|AFAIK that should no longer be the case.
 |> 
 |> Should i open a bug for that ^Z, the ^C inconsistency, and i
 |> do not know, it is a WireGuard VPN within which SSH is used,
 |> and at times no packets get through whatsoever, then no input is
 |> accepted at all, and ^C is not processed, too.
 |
 |I think you are confused.  <newline>~[letter] parsing is in the client
 |character input side, and the server or the link to the server has nothing
 |to do with it.

But input is impossible.  It is stuck.  Not even ^C processing
happens.  And, as i wrote, the code looks for newline (that much
i grasped before posting), and that i cannot input.

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)