#+TITLE: Sync Many Blocks
#+PROPERTY: header-args  :tangle /tmp/default_tangle.txt :comments yes

* Default Tangle

 The =:tangle= target here is given by the ~PROPERTY~ header.  It is
 made up of three parts which synchronize with the tangled destination
 file in 3 different ways as given below: 

** File Contents
 
*** Free Head

#+begin_src conf
  This is some text that can be synced both ways
#+end_src

*** Pull Middle

#+begin_src conf  :tangle-sync import
  The middle text only retrieves from the default tangle file
#+end_src

*** Push tail

#+begin_src conf  :tangle-sync export
  This last piece of text only exports from the source org mode file.
#+end_src

* Desired Function

When =org-babel-tangle= is called, only the [[Free Head]] and [[Push tail]]
sections are tangled. The middle section in the tangled file is
_skipped_.

When =org-babel-detangle= is called, only the [[Pull Middle]] section is
updated here. The other two sections are _skipped_.

* Why skipped?

The functions suffixes explicitly state a direction (=tangle= /
=detangle=), and it's probably important that we retain this
directionality.

If we want to synchronize all blocks (i.e. import the middle section
from the tangled file during =org-babel-tangle=, and export the head
and tail sections during =org-babel-detangle=), then perhaps we set a
specific custom variable =(setq org-babel-tangle-alwayssync t)=?

Or, we create a specific function =org-babel-sync= (for lack of better
name) which tangles/detangles in whatever desired direction the source
block specifies.