[O] Babel - :export-dir and :file-ext arguments cause all blocks to emit files

[Alex Fenton]

Hi,

As far I understand it, |:output-dir| and |:file-ext| that were intended 
to be used in the global document header, applying to all blocks.

However, it seems to mean that all blocks regardless of their :results 
args then emit a file, and put their output as a [file:] link. It's not 
clear from the docs why this happens.

Am I missing something, or does this mean that these arguments are 
useless unless a document happens only to emit graphics from blocks? At 
the moment, the blocks (R, as it happens) are meant to sometimes emit 
scalars, sometimes literal latex, sometimes tables to be formatted by 
orgs, and sometimes graphics. But all the non-graphics are at the moment 
being stuffed into (non-working) PDF files.

Following a discussion and suggested, but not-working solution at: 
https://emacs.stackexchange.com/questions/41618/org-modes-output-dir-and-file-ext-arguments-cause-all-output-to-be-saved-to

Thanks

alex