ref-manual/structure.rst: update the description of local.conf and bblayers.conf

The local.conf file is now mostly empty with the default way of setting
up the environment (with bitbake-setup), and this file is meant to hold
local user configurations, rather than an extensive list of variables.
Adjust the description to reflect the intended way of using this
configuration file.

Also, for both local.conf and bblayers.conf, rephrase the current
usage of the template files (.sample files) to _not_ imply that it is
the default way the OpenEmbedded build system sets things up.

(From yocto-docs rev: 24f24d07fd688825b2ec39dcf0daf8203577f87a)

Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 16 insertions, 20 deletions

diff --git a/documentation/ref-manual/structure.rst b/documentation/ref-manual/structure.rst
index 2640f461d6..a2f2fd4507 100644
--- a/documentation/ref-manual/structure.rst
+++ b/documentation/ref-manual/structure.rst
@@ -269,22 +269,19 @@ This directory should not be shared between builds.
 ``build/conf/local.conf``
 -------------------------
 
-This configuration file contains all the local user configurations for
-your build environment. The ``local.conf`` file contains documentation
-on the various configuration options. Any variable set here overrides
-any variable set elsewhere within the environment unless that variable
-is hard-coded within a file (e.g. by using '=' instead of '?='). Some
-variables are hard-coded for various reasons but such variables are
-relatively rare.
-
-At a minimum, you would normally edit this file to select the target
-:term:`MACHINE`, which package types you wish to use
-(:term:`PACKAGE_CLASSES`), and the location from
-which you want to access downloaded files (:term:`DL_DIR`).
-
-If ``local.conf`` is not present when you start the build, the
-OpenEmbedded build system creates it from ``local.conf.sample`` when you
-``source`` the top-level build environment setup script
+This configuration file contains the local user configurations for the build
+environment.
+
+You could for example experiment with setting (or adding to)
+:term:`DISTRO_FEATURES` or :term:`IMAGE_FEATURES`, or adjust build
+configurations for specific recipes by setting the :term:`PACKAGECONFIG`
+variables for them. If you would like to publish and share changes made to this
+file, it is recommended to put them into a distro :term:`configuration file`, or
+to create layer :term:`configuration fragments <Configuration Fragment>` from
+changes made here.
+
+The :term:`OpenEmbedded Build System` can create it from a ``local.conf.sample``
+file when you ``source`` the top-level build environment setup script
 :ref:`structure-core-script`.
 
 The source ``local.conf.sample`` file used depends on the
@@ -321,12 +318,11 @@ which are directory trees, traversed (or walked) by BitBake. The
 ``bblayers.conf`` file uses the :term:`BBLAYERS`
 variable to list the layers BitBake tries to find.
 
-If ``bblayers.conf`` is not present when you start the build, the
-OpenEmbedded build system creates it from ``bblayers.conf.sample`` when
-you ``source`` the top-level build environment setup script (i.e.
+The OpenEmbedded build system can create it from a ``bblayers.conf.sample`` file
+when you ``source`` the top-level build environment setup script (i.e.
 :ref:`structure-core-script`).
 
-As with the ``local.conf`` file, the source ``bblayers.conf.sample``
+As with the :ref:`structure-build-conf-local.conf` file, the source ``bblayers.conf.sample``
 file used depends on the :term:`TEMPLATECONF` script variable, which
 defaults to ``meta-poky/conf/templates/default`` when you are building from the Yocto
 Project development environment, and to ``meta/conf/templates/default`` when you are