diff --git a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-execution.xml b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-execution.xml
index fa52e29898..b1b72e0aae 100644
--- a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-execution.xml
+++ b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-execution.xml
@@ -42,9 +42,9 @@
$ grep processor /proc/cpuinfo
- This command returns the number of processors, which takes into
- account hyper-threading.
- Thus, a quad-core build host with hyper-threading most likely
+ This command returns the number of processors, which takes into
+ account hyper-threading.
+ Thus, a quad-core build host with hyper-threading most likely
shows eight processors, which is the value you would then assign to
BB_NUMBER_THREADS.
@@ -116,16 +116,35 @@
Prior to parsing configuration files, Bitbake looks
at certain variables, including:
- BB_ENV_WHITELIST
- BB_PRESERVE_ENV
- BB_ENV_EXTRAWHITE
+
+ BB_ENV_WHITELIST
+
+
+ BB_ENV_EXTRAWHITE
+
+
+ BB_PRESERVE_ENV
+
+
+ BB_ORIGENV
+ BITBAKE_UI
- You can find information on how to pass environment variables into the BitBake
- execution environment in the
- "Passing Information Into the Build Task Environment" section.
+ The first four variables in this list relate to how BitBake treats shell
+ environment variables during task execution.
+ By default, BitBake cleans the environment variables and provides tight
+ control over the shell execution environment.
+ However, through the use of these first four variables, you can
+ apply your control regarding the
+ environment variables allowed to be used by BitBake in the shell
+ during execution of tasks.
+ See the
+ "Passing Information Into the Build Task Environment"
+ section and the information about these variables in the
+ variable glossary for more information on how they work and
+ on how to use them.
diff --git a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
index 61daadea92..cfa85b379a 100644
--- a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
+++ b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
@@ -1107,10 +1107,18 @@
Passing Information Into the Build Task Environment
- When running a task, BitBake tightly controls the execution
+ When running a task, BitBake tightly controls the shell execution
environment of the build tasks to make
sure unwanted contamination from the build machine cannot
influence the build.
+
+ By default, BitBake cleans the environment to include only those
+ things exported or listed in its whitelist to ensure that the build
+ environment is reproducible and consistent.
+ You can prevent this "cleaning" by setting the
+ BB_PRESERVE_ENV
+ variable.
+
Consequently, if you do want something to get passed into the
build task environment, you must take these two steps:
@@ -1118,14 +1126,16 @@
Tell BitBake to load what you want from the environment
into the datastore.
You can do so through the
+ BB_ENV_WHITELIST
+ and
BB_ENV_EXTRAWHITE
- variable.
+ variables.
For example, assume you want to prevent the build system from
accessing your $HOME/.ccache
directory.
- The following command tells BitBake to load
- CCACHE_DIR from the environment into
- the datastore:
+ The following command "whitelists" the environment variable
+ CCACHE_DIR causing BitBack to allow that
+ variable into the datastore:
export BB_ENV_EXTRAWHITE="$BB_ENV_EXTRAWHITE CCACHE_DIR"
@@ -1174,12 +1184,6 @@
The previous example returns BAR from the original
execution environment.
-
-
- By default, BitBake cleans the environment to include only those
- things exported or listed in its whitelist to ensure that the build
- environment is reproducible and consistent.
-