Re: bash source code block: problem after ssh commands

[Max Nikulin <manikulin@gmail.com>]

On 18/11/2023 22:51, Matt wrote:
>   ---- On Fri, 17 Nov 2023 23:07:57 +0100  Matt  wrote ---
>> The second claim has nothing to do with Org Babel.  I was able to
>> confirm it and provide the steps to reproduce.  I think it would make
>> sense to report it upstream and let them decide if it's expected
>> behavior.  I'm still happy to do that, but I need to step away from the
>> keyboard :)

> https://lists.gnu.org/archive/html/bug-gnu-emacs/2023-11/msg00976.html
https://debbugs.gnu.org/67259

Notice that the report is for *interactive* sessions. Org babel sessions 
are not so interactive. They are to maintain state, not to interact with 
users directly. Consider

     fakessh() {
         bash -c 'read -t 10 -r; printf "fakessh read: %s\n" "$REPLY"';
     }

     fakessh
     echo next

If you type them in terminal then result depends on delay between 
"fakessh" and "echo next" commands. SSH is an example of command that 
*may* read stdin while its command is running. To avoid ambiguity you 
have to do either

     fakessh </dev/null
     echo next

or

     fakessh <<"EOF"
     echo next
     EOF

"Reproducing" the issue in xterm-like applications or various emacs 
shells makes things even more complicated. Result depends on TERM value 
and if bracketed paste is enabled. With active bracketed paste shell 
knows if you paste single line or a several lines into *shell prompt*, 
so it does not feed second and following lines to first command stdin. 
In the case of

#+begin_src bash :session *ob-shell*
   bash -c 'read -t 10 -r; printf "read: %s\n" "$REPLY"'
   echo next
#+end_src

comint can not guess if all lines are commands or some of them should be 
considered as input to the previous command. Timing or bracketed paste 
are irrelevant for ob-shell sessions.

Possible voluntary decision is to consider every session source block 
similar to "C-x C-e" in bash prompt, so nothing should become implicit 
stdin of commands. Content of a source block should be saved into a 
temporary file then "source /path/to/block_content" command should be 
send to the session buffer. Likely command depends on shell.