How to run the tangled file?

Question

How does one run the arbitrary command to execute the tangled code? I use Emacs both on Windows and Linux, but currently I need to run the generated batch file in particular Windows environment.
Here is how the block looks like:

#+begin_src bat :exports both :tangle "run_tests.bat"
...
#+end_src

I have a batch file which sets the environment (d:\Programs\Microsoft Visual Studio 12.0\VC\vcvarsall.bat), but cannot run my tangled file inside this new environment. How to do this?

The code can be tangled using org-babel-tangle of course, but I cannot run the generated batch file from Emacs using org-ctrl-c-ctrl-c as it says:

org-babel-execute-src-block: No org-babel-execute function for bat!

Any help would be appreciated.

Answer 1

Tangling creates the batch file, execution of source block tries to execute the source block in the specified language (and there is no ob-bat I know of).

You can execute the tangled batch file in a shell source block. Therefore add the following to your org file:

#+BEGIN_SRC sh :exports results :results output
cmd /c ""d:\Programs\Microsoft Visual Studio 12.0\VC\vcvarsall.bat" & run_tests.bat"
#+END_SRC

This first runs the batch and then, separated by &, your batch script.

Note that I have a MinGW environment with a bash shell. If you want to run windows cmd.exe directly you may find a hint here, which introduces a shcmd header option.

Also, you need to require ob-sh or ob-shell, depending on your org version. Therefore I do:

(unless (require 'ob-sh nil 'noerror)
  (require 'ob-shell))

Btw, if all you want is to execute some command sequence you can simply do:

#+BEGIN_SRC sh :exports results :results output
call "d:\Programs\Microsoft Visual Studio 12.0\VC\vcvarsall.bat"
echo "insert commands here"
#+END_SRC

EDIT:

Since I may need a windows native execution facility in org-mode I will write an ob-bat.el as soon as I am back from holiday (next week). Meanwhile you may try this code snippet (since I have no windows box it is untested):

(require 'ob)
(require 'ob-shell)

(defvar org-babel-tangle-lang-exts)
(add-to-list 'org-babel-tangle-lang-exts '("bat" . "bat"))

(defcustom org-babel-bat-command "cmd.exe"
  "Name of command to use for executing bat code.")

(defun org-babel-execute:bat (body params)
  "Execute a block of bat code with cmd.exe.
This function is called by `org-babel-execute-src-block'."
  (let ((shell-file-name org-babel-bat-command))
    (org-babel-execute:shell body params)))

(provide 'ob-bat)

With this you should be able to execute bat source blocks:

#+BEGIN_SRC bat :exports results :results output
echo hello
#+END_SRC