Devtool

The devtool command-line utility provides several features that help you build, test, and package software in Yocto environments.
This command is available alongside bitbake and is an essential tool for recipe development and maintenance.

This page provides a Quick Reference for the devtool command.

Getting Started

Before using devtool, you must set up the BitBake environment as described in your BSP setup instructions.

Once the environment is ready, run the following command to list all available subcommands:

devtool --help

The Workspace Layer Structure

devtool uses a workspace layer to manage source code and recipes under development. This workspace is a shared working area used by multiple devtool commands.

Below is the typical structure of the workspace layer:

../build-directory
    └── workspace
        ├── attic
        ├── conf
        ├── appends
        │   └── recipe.bbappend
        ├── README
        ├── recipes
        │   └── recipe-name
        │       └── recipe-name.bb
        └── sources
            └── recipe-name
                ├── folders
                ├── files
                .
                .

Directory Overview

Folder	Description
attic	Created when running `devtool reset`, used to temporarily preserve files.
conf	Contains configuration files, including `layer.conf`.
appends	Holds `.bbappend` files pointing to external sources.
README	Describes the contents of the workspace and basic management info.
recipes	Contains recipe directories; each folder corresponds to a recipe.
sources	Contains working copies of the source trees used in builds.

Adding a New Recipe

Use the devtool add command to create and add a new recipe to the workspace layer. The recipe should not already exist — devtool will generate it for you.

The general syntax is:

devtool add <new-recipe-name> <source-files-path>

Example:

devtool add engicam /home/user/sources/engicam

If the workspace layer does not exist, devtool creates and populates it automatically. If it already exists, the new recipe, append files, and source tree are added within the existing workspace.

Note

If your recipe has runtime dependencies, make sure the required packages are installed on the target hardware. Missing libraries or dependencies will cause your application to fail when executed.

Modifying an Existing Recipe

The devtool modify command lets you customize the source code of an existing recipe.

This command:

Extracts the source of a recipe
Sets it up as a Git repository (if not already one)
Checks out a development branch (devtool)
Applies any existing patches as commits

Syntax:

devtool modify <recipe-name>

Example — modifying the Linux kernel or U-Boot source:

devtool modify linux-engicam
devtool modify u-boot-engicam

After running the command, devtool uses the recipe’s SRC_URI to fetch and extract sources into the workspace. You can then edit, build, and test your changes directly from the extracted source tree.

Updating a Recipe

Use the devtool update-recipe command to update an existing recipe with patches that represent your code modifications.

Typical workflow:

Extract sources using devtool modify
Make your changes and test the build
Commit your changes in Git
Run devtool update-recipe to generate patches and update the recipe

Syntax:

devtool update-recipe <recipe-name>

Tip

If you run devtool update-recipe without committing your changes, they will be ignored.

If you prefer to keep your changes in a custom layer rather than modifying the original recipe, use the -a or --append option:

devtool update-recipe <recipe-name> -a <base-layer-directory>

This creates a .bbappend file in the specified layer path. If an append file already exists, it will be updated accordingly.

Tip

To learn how to create your own meta-layer, refer to the Creating a New Meta-Layer guide.