.. _reference_variables:

Special variables
=================

Some variables have a hard coded meaning. They begins and ends with
``__``. Here is the list:

* ``__subdir__``: the result will be placed is a subdirectory of the output
  directory. The value can contain the following strings:

  - {fid} = file ID
  - {parent} = name of the parent directory

* ``__no_cache__``: no cache is used.

* ``__no_check__``: no XML or ePub file is executed but forced ones.

* ``__no_remove__``: temporary files are kept.

* ``__zip__``: the result is compressed in one ZIP file. if ``__zip__`` contains
  a ``.``, it is used as an extension. In this case, you can use ``{timestamp}``
  for time stamping your archive.

* ``__assembly__``: the `cioset` file is interpreted as an assembly.

* ``__resources__``: the value is comma separated pathes of resource
  directories. These are used as a priority. The value can use the following
  string:

  - {fpath} = path of current file

* ``__template__``: it defines a directory containing templates for the
  processor. This value overrided default value. It matches the following
  pattern: ``<id>:<path>``. Ex: sandbox:Templates

You can use variables to manage breakpoints in your process. We recommend to
call this kind of variable ``__breakpointX__`` where ``X`` is the number of the
break point.