commit f6db12902654112c628e24c8a7d3db1a9380de4a
parent 1705d793ae70e73dfa5adca546dedbe196fbca46
Author: Marcello Stanisci <marcello.stanisci@inria.fr>
Date: Thu, 15 Dec 2016 15:37:25 +0100
$-expansion in config
Diffstat:
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/configuration-basics.rst b/configuration-basics.rst
@@ -39,11 +39,13 @@ its `values`. The right format follows::
value21 = string
value22 = /path22
-Throught any configuration file, it is possible to use ``$``-prefixed variables,
-especially when a value needs a pathname. Some of them are automatically resolved,
-like ``${TALER_DATA_HOME}``, ``${TALER_RUNTIME_DIR}``, or ``${HOME}``. (FIXME: explain
-how/where/when those defaults get resolved) Other variables can be defined under the
-`paths` section. For example::
+Throughout any configuration file, it is possible to use ``$``-prefixed variables,
+like ``$VAR``, especially when they represent filesystem paths.
+It is also possible to provide defaults values for those variables that are unset,
+by using the following syntax: ``${VAR:-default}``.
+However, there are two ways a user can set ``$``-prefixable variables:
+
+by defining them under a ``[paths]`` section, see example below, ::
[paths]
TALER_DEPLOYMENT_SHARED = ${HOME}/shared-data
@@ -51,8 +53,17 @@ how/where/when those defaults get resolved) Other variables can be defined under
[section-x]
path-x = ${TALER_DEPLOYMENT_SHARED}/x
-The utility ``taler-config``, which gets installed along with the exchange, serves to get and
-set configuration values without directly editing the `.conf`. See ``taler-config --help``.
+or by setting them in the environment::
+
+ $ export VAR=/x
+
+The configuration loader will give precedence to variables set under ``[path]``,
+though.
+
+The utility ``taler-config``, which gets installed along with the exchange, serves
+to get and set configuration values without directly editing the `.conf`.
+The option ``-f`` is particularly useful to resolve pathnames, when they use
+several levels of ``$``-expanded variables. See ``taler-config --help``.
Note that, in this stage of development, the file ``$HOME/.config/taler.conf``
can contain sections for *all* the component. For example, both an exchange and
