Re: org-babel: interactive terminal support

[Benjamin Andresen <benny@in-ulm.de>]

Hey Dan,

Dan Davison <davison@stats.ox.ac.uk> writes:

> Hi Benny,
>
> This looks very interesting and I think it's extremely likely that we'll
> want to include your code -- thanks very much. Having said that, I'm
> being a bit dense: would you mind expanding a bit on what this currently
> does, and what it has the potential to do?

All it currently does it show you a terminal which gets the source
code block send to. Just like an inferior process.

I've made a gif of the channels.org example from my first mail:
http://github.com/bandresen/org-babel-screen/blob/master/channels.anim.gif

The way I currently see it, it somehow works as an interactive makefile.

An example of a use that I have is that want to extract several frames
out of a video file and convert them to a gif animation.

It's a commented org file with several steps such as:

* find the part you want to extract
#+begin_src screen :session create-gif
  mplayer -ao null -osdlevel 3 /tmp/videofile.avi 
#+end_src
[...snip...]
* convert selected frames to gif
#+begin_src screen :session create-gif
  convert -delay 100 -loop 0 .qiv-select/* animation.gif
#+end_src

I don't know how useful it is to other people, but because it basically
gives you the power over a terminal emulator you could do anything in it
that you can do in a normal terminal. Except better controlled and
documented.

Or one could use a standardized notation for keypresses and let screen
translate them for you. Example:

#+begin_src screen :session vimtutorial
  vimtutor
  85G
  fcx
  EEx
  llx
  ^Vjjjjlllx
#+end_src

Which might be useful in some way.

Another thing that might be possible is to simulate an 'expect' like
behavior by using screen's capability to dump the output of commands.
It's certainly possible, but replacing an app like 'expect' is no small
task. :-)

br,
benny