kw env

Introduction

Inspired by Ruby RVM and Python Env, kw has a feature that enables developers to create environments for their context and quickly switches between them. For example, in the same kernel, the developer might want to work with ARM and X86, and kw env can be an excellent way to switch between these two contexts.

When kw creates a new env, it isolates:

* The .config file
* All kw config
* Build files

As a result, env feature must interoperate with these features:

* Build
* Deploy
* Kernel config

Create a new env

Let’s say that you have a fresh new kernel ready to be compiled, and you started your kw config by using:

kw init

Now you want to create a new env to maintain the specific configuration you can use:

kw env --create <ENV_NAME>

For example:

kw env --create X86_64_CONFIG_TO_TEST_MACHINE_Y

When you create a new env, it will instantiate the current config to the new env. Every change you make in the kw configurations will be contained in the current config. For example, you can change your build or remote options, and after that, create a new env:

kw env --create X86_32_CONFIG_TO_TEST_MACHINE_P

Switch between envs

Let’s say that you want to switch from one config to another, you can just use:

kw env --use X86_32_CONFIG_TO_TEST_MACHINE_P

If you want to check if everything looks correct, you can use:

kw vars

How to customize your bash terminal to display the current environment

This feature lets users view the current kw environment (if you have one) in their bash terminal via the PS1 variable. It is especially useful when working with multiple kw envs, as it helps you stay aware of the context you are working in.

To enable this functionality, follow these steps:

If you did not install kw yet, run the below command; otherwise, go to the next step:

./setup -i

Enable the functionality to show the current environment in the bash terminal by running the following command:

./setup -s

Once enabled, you need to add the following line to the .bashrc file:

PS1="${PS1/\\$/}" && PS1+="\$(kw_get_current_env_name)$ "

Note

If you have modified the PS1 variable in the .bashrc file, you will need to adapt it to work correctly. You can simply call the kw_get_current_env_name function on PS1 to display the current environment being used in kworkflow.