I wrote a piece of code like below:

#+NAME: inc-file
#+BEGIN_SRC elisp :results value raw :exports results :var file="common.inc.org"
  (concat "#+INCLUDE: /path/to/include-dir/" file) ;; path is cal-ed from path of current-buffer file
#+END_SRC

#+CALL: inc-file(file="a.org") :results raw

but this does not work, anyone knows why?

By the way, #+HTML_HEAD in code block results works well:

#+NAME: d-header
#+BEGIN_SRC elisp :results value raw :exports results
  (concat "#+HTML_HEAD: <link rel=\"stylesheet\" type=\"text/css\" href=\"" "/style.css" "\" />")
#+END_SRC

#+CALL: d-header() :results raw


Thanks.

--
--