Dear Sebastien and Eric, Thanks a lot for your kind replies. However, this is not yet quite what I am after.
I want to be able to manually execute each code block, but not automatically whenever the whole document is rendered. So, I would always switch on/off "eval never". Hm... I will try out the ":cache" header argument. However, again this does not work so well, because for the languages I am using the :file argument does not work very well (I have to manually change extensions, so I include the resulting file links by hand anyway and set :results to silent. So, I it sounds like few org-babel users is really running larger applications in their code blocks which can delay the export of the whole document considerably. Anyway, thanks a lot for your feedback. Best wishes, Torsten
