home.public.snippits/home/public/snippits/org/babel-sh.org

• Simple command, set a variable
• Simple command, read variable set
• Setup - Don't ask about resetting the session
• Reset the session :results output

Demonstrate use of sessions with bash in org babel.

Simple command, set a variable

Get basics about the shell, etc. Set a varable

date
echo SHELL is $SHELL
echo BASH_VERSION is $BASH_VERSION
echo PID is $$
SET_IN_FIRST_BLOCK=something

Wed Nov 16 07:45:29 AM EST 2022
SHELL is /bin/bash
BASH_VERSION is 5.1.16(1)-release
PID is 73788

Simple command, read variable set

Get pid. Should be same as previous example.

See if the variable exists

date
echo PID is $$
[[ -v SET_IN_FIRST_BLOCK ]] && \
    echo SET_IN_FIRST_BLOCK is $SET_IN_FIRST_BLOCK || \
        echo SET_IN_FIRST_BLOCK is not defined

Wed Nov 16 07:45:32 AM EST 2022
PID is 73788
> > SET_IN_FIRST_BLOCK is something

Setup - Don't ask about resetting the session

Pay no attention to that man behind the curtain.

This is emacs lisp foo that turn of prompting when killing the buffer running the shell.

  (setq kill-buffer-query-functions
    (remq 'process-kill-buffer-query-function
           kill-buffer-query-functions))

Reset the session :results output

Kill the TEST session. Variables, PID should reset.

https://emacs.stackexchange.com/questions/5293/how-to-force-an-org-babel-session-to-reset-or-initialize

PS1="$ "
date
echo TEST session killed
echo PID is $$

[[ -v SET_IN_FIRST_BLOCK ]] && \
  echo SET_IN_FIRST_BLOCK is $SET_IN_FIRST_BLOCK || \
      echo SET_IN_FIRST_BLOCK is not defined

gmj@mx:$ Wed Nov 16 07:45:39 AM EST 2022
TEST session killed
PID is 73860
gmj@mx:$ > > SET_IN_FIRST_BLOCK is not defined