Use .zephyrrc for initializing common variables

The file can be used to define variables used by the SDK to avoid
having to define them everytime a session is started.

The old file names ~/zephyr-env_install.bash will still work but
it will warn about the file being renamed. We do not want to break
users who have ~/zephyr-env_install.bash in their home and depend on
it.

Change-Id: I04fcaa76854bda3dcfc1cabe75e00e95c511b10d
Signed-off-by: Anas Nashif <anas.nashif@intel.com>

doc/getting_started/installation_linux.rst

@@ -182,6 +182,16 @@ Follow these steps to install the SDK on your Linux host system.
 
        $ export ZEPHYR_SDK_INSTALL_DIR=/opt/zephyr-sdk
 
+  To use the same toolchain in new sessions in the future you can set the
+  variables in the file :file:`${HOME}/.zephyrrc`, for example:
+
+  .. code-block:: console
+
+     $ cat <<EOF > ~/.zephyrrc
+     export ZEPHYR_GCC_VARIANT=zephyr
+     export ZEPHYR_SDK_INSTALL_DIR=/opt/zephyr-sdk
+     EOF
+
 .. _SDK self-extractable binary:
    https://nexus.zephyrproject.org/content/repositories/releases/org/zephyrproject/zephyr-sdk/0.7.2-i686/zephyr-sdk-0.7.2-i686-setup.run
 

doc/getting_started/installation_mac.rst

@@ -174,6 +174,16 @@ and use the target location where the toolchain was installed, type:
    $ export ZEPHYR_SDK_INSTALL_DIR=/Volumes/CrossToolNG/x-tools
 
 
+To use the same toolchain in new sessions in the future you can set the
+variables in the file :file:`${HOME}/.zephyrrc`, for example:
+
+.. code-block:: console
+
+   $ cat <<EOF > ~/.zephyrrc
+   export ZEPHYR_SDK_INSTALL_DIR=/Volumes/CrossToolNG/x-tools
+   export ZEPHYR_GCC_VARIANT=xtools
+   EOF
+
 .. _Homebrew site: http://brew.sh/
 
 .. _crosstool-ng site: http://crosstool-ng.org

zephyr-env.sh

@@ -20,5 +20,11 @@ unset scripts_path
 
 # enable custom environment settings
 zephyr_answer_file=~/zephyr-env_install.bash
-[ -f ${zephyr_answer_file} ] && . ${zephyr_answer_file}
+[ -f ${zephyr_answer_file} ] && {
+	echo "Warning: Please rename ~/zephyr-env_install.bash to ~/.zephyrrc";
+	. ${zephyr_answer_file};
+}
+unset zephyr_answer_file
+zephyr_answer_file=~/.zephyrrc
+[ -f ${zephyr_answer_file} ] &&  . ${zephyr_answer_file};
 unset zephyr_answer_file