Re: bash source code block: problem after ssh commands

[Leo Butler]

On Wed, Oct 25 2023, Alain.Cochard@unistra.fr wrote:

> Hello.
>
> For me, 'C-c C-c' on the following group
>
>    #+begin_src bash :results output
>    echo "foo"
>    echo "bar"
>    #+end_src
>
>
> works as I expect: 'foo' and 'bar' are echo'ed.  But it fails on this
> one:
>
>    #+begin_src bash :results output
>    ssh cochard@fruc.u-strasbg.fr "echo foo>foo_file"
>    echo "bar"
>    #+end_src
>
>
> The file 'foo_file' is created on the remote machine, but 'bar' is not
> echo'ed.  I have tried to insert other commands between the ssh and
> echo commands, or append semicolons at the end of the commands,
> without success.
>
> By contrast, it works with this one:
>
>    #+begin_src bash :results output
>    ssh cochard@fruc.u-strasbg.fr "echo foo>foo_file" ; echo "bar"
>    #+end_src
>
> Perhaps it is worth noting that I observe the same behavior if I
> simply copy/yank the commands (I mean: the two commands yank'ed at
> once) in an emacs terminal (obtained with 'M-x shell').  However,
> everything works as I expect if I copy/yank the commands (all at once)
> in a "regular" X terminal (xfce in my case).

It looks like an issue in comint-mode and the way that it is handling
the temporary ssh session. This is not an issue with org-mode.

Here are a couple work-arounds:

- add the -f to the ssh command
- add a semi-colon and line continuation to the first line.

Working examples:

#+begin_src bash :results output
  ssh -f SSH-HOST 'echo foo>/tmp/foo_file'
  echo $(uname -a) |tee /tmp/uname.txt
#+end_src

#+RESULTS:
: Linux t14 6.5.0-1-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.5.3-1 (2023-09-13) 
x86_64 GNU/Linux

#+begin_src bash :results output
  ssh pearce-120 'echo foo>/tmp/foo_file' &&\
  echo $(uname -a) | tee /tmp/uname.txt
#+end_src

#+RESULTS:
: Linux t14 6.5.0-1-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.5.3-1 (2023-09-13) 
x86_64 GNU/Linux

Not working:

#+begin_src bash :results output
  ssh SSH-HOST 'echo foo>/tmp/foo_file'
  echo $(uname -a) |tee /tmp/uname1.txt
#+end_src

If you look at /tmp after running the third example, you see that that
second command line has not been executed.

Leo